Release v1.6.0 (#324)

* Update version and changelog for v1.6.0
* Update docs
diff --git a/docs/dyn/compute_beta.instanceGroupManagers.html b/docs/dyn/compute_beta.instanceGroupManagers.html
index 8c93a0e..1cb21a2 100644
--- a/docs/dyn/compute_beta.instanceGroupManagers.html
+++ b/docs/dyn/compute_beta.instanceGroupManagers.html
@@ -99,7 +99,7 @@
   <code><a href="#list">list(project, zone, orderBy=None, maxResults=None, pageToken=None, filter=None)</a></code></p>
 <p class="firstline">Retrieves a list of managed instance groups that are contained within the specified project and zone.</p>
 <p class="toc_element">
-  <code><a href="#listManagedInstances">listManagedInstances(project, zone, instanceGroupManager)</a></code></p>
+  <code><a href="#listManagedInstances">listManagedInstances(project, zone, instanceGroupManager, order_by=None, maxResults=None, pageToken=None, filter=None)</a></code></p>
 <p class="firstline">Lists all of the instances in the managed instance group. Each instance in the list has a currentAction, which indicates the action that the managed instance group is performing on the instance. For example, if the group is still creating an instance, the currentAction is CREATING. If a previous action failed, the list displays the errors for that failed action.</p>
 <p class="toc_element">
   <code><a href="#list_next">list_next(previous_request, previous_response)</a></code></p>
@@ -190,7 +190,7 @@
     },
     "endTime": "A String", # [Output Only] The time that this operation was completed. This value is in RFC3339 text format.
     "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
-    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. If creating a persistent disk snapshot, this points to the persistent disk that the snapshot was created from.
+    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. For operations related to creating a snapshot, this points to the persistent disk that the snapshot was created from.
   }</pre>
 </div>
 
@@ -253,13 +253,14 @@
               "zone": "A String", # [Output Only] The URL of the zone where the managed instance group is located (for zonal resources).
               "autoHealingPolicies": [ # The autohealing policy for this managed instance group. You can specify only one value.
                 {
-                  "healthCheck": "A String", # The URL for the HealthCheck that signals autohealing.
+                  "healthCheck": "A String", # The URL for the health check that signals autohealing.
                   "initialDelaySec": 42, # The number of seconds that the managed instance group waits before it applies autohealing policies to new instances or recently recreated instances. This initial delay allows instances to initialize and run their startup scripts before the instance group determines that they are UNHEALTHY. This prevents the managed instance group from recreating its instances prematurely. This value must be from range [0, 3600].
                 },
               ],
               "targetSize": 42, # The target number of running instances for this managed instance group. Deleting or abandoning instances reduces this number. Resizing the group changes this number.
               "failoverAction": "A String", # The action to perform in case of zone failure. Only one value is supported, NO_FAILOVER. The default is NO_FAILOVER.
               "instanceGroup": "A String", # [Output Only] The URL of the Instance Group resource.
+              "serviceAccount": "A String", # Service account will be used as credentials for all operations performed by managed instance group on instances. The service accounts needs all permissions required to create and delete instances. When not specified, the service account {projectNumber}@cloudservices.gserviceaccount.com will be used.
               "kind": "compute#instanceGroupManager", # [Output Only] The resource type, which is always compute#instanceGroupManager for managed instance groups.
               "targetPools": [ # The URLs for all TargetPool resources to which instances in the instanceGroup field are added. The target pools automatically apply to all of the instances in the managed instance group.
                 "A String",
@@ -357,7 +358,7 @@
     },
     "endTime": "A String", # [Output Only] The time that this operation was completed. This value is in RFC3339 text format.
     "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
-    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. If creating a persistent disk snapshot, this points to the persistent disk that the snapshot was created from.
+    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. For operations related to creating a snapshot, this points to the persistent disk that the snapshot was created from.
   }</pre>
 </div>
 
@@ -425,7 +426,7 @@
     },
     "endTime": "A String", # [Output Only] The time that this operation was completed. This value is in RFC3339 text format.
     "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
-    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. If creating a persistent disk snapshot, this points to the persistent disk that the snapshot was created from.
+    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. For operations related to creating a snapshot, this points to the persistent disk that the snapshot was created from.
   }</pre>
 </div>
 
@@ -458,13 +459,14 @@
       "zone": "A String", # [Output Only] The URL of the zone where the managed instance group is located (for zonal resources).
       "autoHealingPolicies": [ # The autohealing policy for this managed instance group. You can specify only one value.
         {
-          "healthCheck": "A String", # The URL for the HealthCheck that signals autohealing.
+          "healthCheck": "A String", # The URL for the health check that signals autohealing.
           "initialDelaySec": 42, # The number of seconds that the managed instance group waits before it applies autohealing policies to new instances or recently recreated instances. This initial delay allows instances to initialize and run their startup scripts before the instance group determines that they are UNHEALTHY. This prevents the managed instance group from recreating its instances prematurely. This value must be from range [0, 3600].
         },
       ],
       "targetSize": 42, # The target number of running instances for this managed instance group. Deleting or abandoning instances reduces this number. Resizing the group changes this number.
       "failoverAction": "A String", # The action to perform in case of zone failure. Only one value is supported, NO_FAILOVER. The default is NO_FAILOVER.
       "instanceGroup": "A String", # [Output Only] The URL of the Instance Group resource.
+      "serviceAccount": "A String", # Service account will be used as credentials for all operations performed by managed instance group on instances. The service accounts needs all permissions required to create and delete instances. When not specified, the service account {projectNumber}@cloudservices.gserviceaccount.com will be used.
       "kind": "compute#instanceGroupManager", # [Output Only] The resource type, which is always compute#instanceGroupManager for managed instance groups.
       "targetPools": [ # The URLs for all TargetPool resources to which instances in the instanceGroup field are added. The target pools automatically apply to all of the instances in the managed instance group.
         "A String",
@@ -513,13 +515,14 @@
     "zone": "A String", # [Output Only] The URL of the zone where the managed instance group is located (for zonal resources).
     "autoHealingPolicies": [ # The autohealing policy for this managed instance group. You can specify only one value.
       {
-        "healthCheck": "A String", # The URL for the HealthCheck that signals autohealing.
+        "healthCheck": "A String", # The URL for the health check that signals autohealing.
         "initialDelaySec": 42, # The number of seconds that the managed instance group waits before it applies autohealing policies to new instances or recently recreated instances. This initial delay allows instances to initialize and run their startup scripts before the instance group determines that they are UNHEALTHY. This prevents the managed instance group from recreating its instances prematurely. This value must be from range [0, 3600].
       },
     ],
     "targetSize": 42, # The target number of running instances for this managed instance group. Deleting or abandoning instances reduces this number. Resizing the group changes this number.
     "failoverAction": "A String", # The action to perform in case of zone failure. Only one value is supported, NO_FAILOVER. The default is NO_FAILOVER.
     "instanceGroup": "A String", # [Output Only] The URL of the Instance Group resource.
+    "serviceAccount": "A String", # Service account will be used as credentials for all operations performed by managed instance group on instances. The service accounts needs all permissions required to create and delete instances. When not specified, the service account {projectNumber}@cloudservices.gserviceaccount.com will be used.
     "kind": "compute#instanceGroupManager", # [Output Only] The resource type, which is always compute#instanceGroupManager for managed instance groups.
     "targetPools": [ # The URLs for all TargetPool resources to which instances in the instanceGroup field are added. The target pools automatically apply to all of the instances in the managed instance group.
       "A String",
@@ -587,7 +590,7 @@
     },
     "endTime": "A String", # [Output Only] The time that this operation was completed. This value is in RFC3339 text format.
     "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
-    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. If creating a persistent disk snapshot, this points to the persistent disk that the snapshot was created from.
+    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. For operations related to creating a snapshot, this points to the persistent disk that the snapshot was created from.
   }</pre>
 </div>
 
@@ -638,13 +641,14 @@
           "zone": "A String", # [Output Only] The URL of the zone where the managed instance group is located (for zonal resources).
           "autoHealingPolicies": [ # The autohealing policy for this managed instance group. You can specify only one value.
             {
-              "healthCheck": "A String", # The URL for the HealthCheck that signals autohealing.
+              "healthCheck": "A String", # The URL for the health check that signals autohealing.
               "initialDelaySec": 42, # The number of seconds that the managed instance group waits before it applies autohealing policies to new instances or recently recreated instances. This initial delay allows instances to initialize and run their startup scripts before the instance group determines that they are UNHEALTHY. This prevents the managed instance group from recreating its instances prematurely. This value must be from range [0, 3600].
             },
           ],
           "targetSize": 42, # The target number of running instances for this managed instance group. Deleting or abandoning instances reduces this number. Resizing the group changes this number.
           "failoverAction": "A String", # The action to perform in case of zone failure. Only one value is supported, NO_FAILOVER. The default is NO_FAILOVER.
           "instanceGroup": "A String", # [Output Only] The URL of the Instance Group resource.
+          "serviceAccount": "A String", # Service account will be used as credentials for all operations performed by managed instance group on instances. The service accounts needs all permissions required to create and delete instances. When not specified, the service account {projectNumber}@cloudservices.gserviceaccount.com will be used.
           "kind": "compute#instanceGroupManager", # [Output Only] The resource type, which is always compute#instanceGroupManager for managed instance groups.
           "targetPools": [ # The URLs for all TargetPool resources to which instances in the instanceGroup field are added. The target pools automatically apply to all of the instances in the managed instance group.
             "A String",
@@ -672,13 +676,17 @@
 </div>
 
 <div class="method">
-    <code class="details" id="listManagedInstances">listManagedInstances(project, zone, instanceGroupManager)</code>
+    <code class="details" id="listManagedInstances">listManagedInstances(project, zone, instanceGroupManager, order_by=None, maxResults=None, pageToken=None, filter=None)</code>
   <pre>Lists all of the instances in the managed instance group. Each instance in the list has a currentAction, which indicates the action that the managed instance group is performing on the instance. For example, if the group is still creating an instance, the currentAction is CREATING. If a previous action failed, the list displays the errors for that failed action.
 
 Args:
   project: string, Project ID for this request. (required)
   zone: string, The name of the zone where the managed instance group is located. (required)
   instanceGroupManager: string, The name of the managed instance group. (required)
+  order_by: string, A parameter
+  maxResults: integer, A parameter
+  pageToken: string, A parameter
+  filter: string, A parameter
 
 Returns:
   An object of the form:
@@ -792,7 +800,7 @@
     },
     "endTime": "A String", # [Output Only] The time that this operation was completed. This value is in RFC3339 text format.
     "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
-    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. If creating a persistent disk snapshot, this points to the persistent disk that the snapshot was created from.
+    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. For operations related to creating a snapshot, this points to the persistent disk that the snapshot was created from.
   }</pre>
 </div>
 
@@ -852,7 +860,7 @@
     },
     "endTime": "A String", # [Output Only] The time that this operation was completed. This value is in RFC3339 text format.
     "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
-    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. If creating a persistent disk snapshot, this points to the persistent disk that the snapshot was created from.
+    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. For operations related to creating a snapshot, this points to the persistent disk that the snapshot was created from.
   }</pre>
 </div>
 
@@ -927,7 +935,7 @@
     },
     "endTime": "A String", # [Output Only] The time that this operation was completed. This value is in RFC3339 text format.
     "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
-    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. If creating a persistent disk snapshot, this points to the persistent disk that the snapshot was created from.
+    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. For operations related to creating a snapshot, this points to the persistent disk that the snapshot was created from.
   }</pre>
 </div>
 
@@ -945,7 +953,7 @@
 {
     "autoHealingPolicies": [
       {
-        "healthCheck": "A String", # The URL for the HealthCheck that signals autohealing.
+        "healthCheck": "A String", # The URL for the health check that signals autohealing.
         "initialDelaySec": 42, # The number of seconds that the managed instance group waits before it applies autohealing policies to new instances or recently recreated instances. This initial delay allows instances to initialize and run their startup scripts before the instance group determines that they are UNHEALTHY. This prevents the managed instance group from recreating its instances prematurely. This value must be from range [0, 3600].
       },
     ],
@@ -998,7 +1006,7 @@
     },
     "endTime": "A String", # [Output Only] The time that this operation was completed. This value is in RFC3339 text format.
     "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
-    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. If creating a persistent disk snapshot, this points to the persistent disk that the snapshot was created from.
+    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. For operations related to creating a snapshot, this points to the persistent disk that the snapshot was created from.
   }</pre>
 </div>
 
@@ -1064,7 +1072,7 @@
     },
     "endTime": "A String", # [Output Only] The time that this operation was completed. This value is in RFC3339 text format.
     "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
-    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. If creating a persistent disk snapshot, this points to the persistent disk that the snapshot was created from.
+    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. For operations related to creating a snapshot, this points to the persistent disk that the snapshot was created from.
   }</pre>
 </div>
 
@@ -1133,7 +1141,7 @@
     },
     "endTime": "A String", # [Output Only] The time that this operation was completed. This value is in RFC3339 text format.
     "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
-    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. If creating a persistent disk snapshot, this points to the persistent disk that the snapshot was created from.
+    "targetLink": "A String", # [Output Only] The URL of the resource that the operation modifies. For operations related to creating a snapshot, this points to the persistent disk that the snapshot was created from.
   }</pre>
 </div>