Release v1.6.0 (#324)

* Update version and changelog for v1.6.0
* Update docs
diff --git a/docs/dyn/compute_beta.projects.html b/docs/dyn/compute_beta.projects.html
index 4dda76f..11caddc 100644
--- a/docs/dyn/compute_beta.projects.html
+++ b/docs/dyn/compute_beta.projects.html
@@ -78,6 +78,12 @@
   <code><a href="#get">get(project)</a></code></p>
 <p class="firstline">Returns the specified Project resource.</p>
 <p class="toc_element">
+  <code><a href="#getXpnHost">getXpnHost(project)</a></code></p>
+<p class="firstline">Get the XPN host project that this project links to. May be empty if no link exists.</p>
+<p class="toc_element">
+  <code><a href="#listXpnHosts">listXpnHosts(project, body)</a></code></p>
+<p class="firstline">List all XPN host projects visible to the user in an organization.</p>
+<p class="toc_element">
   <code><a href="#moveDisk">moveDisk(project, body)</a></code></p>
 <p class="firstline">Moves a persistent disk from one zone to another.</p>
 <p class="toc_element">
@@ -125,9 +131,9 @@
     ],
     "name": "A String", # The project ID. For example: my-example-project. Use the project ID to make requests to Compute Engine.
     "usageExportLocation": { # The location in Cloud Storage and naming method of the daily usage report. Contains bucket_name and report_name prefix. # The naming prefix for daily usage reports and the Google Cloud Storage bucket where they are stored.
-        "bucketName": "A String", # The name of an existing bucket in Cloud Storage where the usage report object is stored. The Google Service Account is granted write access to this bucket. This can either be the bucket name by itself, such as example-bucket, or the bucket name with gs:// or https://storage.googleapis.com/ in front of it, such as gs://example-bucket.
-        "reportNamePrefix": "A String", # An optional prefix for the name of the usage report object stored in bucketName. If not supplied, defaults to usage. The report is stored as a CSV file named report_name_prefix_gce_YYYYMMDD.csv where YYYYMMDD is the day of the usage according to Pacific Time. If you supply a prefix, it should conform to Cloud Storage object naming conventions.
-      },
+      "bucketName": "A String", # The name of an existing bucket in Cloud Storage where the usage report object is stored. The Google Service Account is granted write access to this bucket. This can either be the bucket name by itself, such as example-bucket, or the bucket name with gs:// or https://storage.googleapis.com/ in front of it, such as gs://example-bucket.
+      "reportNamePrefix": "A String", # An optional prefix for the name of the usage report object stored in bucketName. If not supplied, defaults to usage. The report is stored as a CSV file named report_name_prefix_gce_YYYYMMDD.csv where YYYYMMDD is the day of the usage according to Pacific Time. If you supply a prefix, it should conform to Cloud Storage object naming conventions.
+    },
     "xpnProjectStatus": "A String", # [Output Only] The role this project has in a Cross Project Network (XPN) configuration. Currently only HOST projects are differentiated.
     "creationTimestamp": "A String", # [Output Only] Creation timestamp in RFC3339 text format.
     "id": "A String", # [Output Only] The unique identifier for the resource. This identifier is defined by the server. This is not the project ID, and is just a unique ID used by Compute Engine to identify resources.
@@ -137,6 +143,113 @@
 </div>
 
 <div class="method">
+    <code class="details" id="getXpnHost">getXpnHost(project)</code>
+  <pre>Get the XPN host project that this project links to. May be empty if no link exists.
+
+Args:
+  project: string, Project ID for this request. (required)
+
+Returns:
+  An object of the form:
+
+    { # A Project resource. Projects can only be created in the Google Cloud Platform Console. Unless marked otherwise, values can only be modified in the console.
+    "kind": "compute#project", # [Output Only] Type of the resource. Always compute#project for projects.
+    "defaultServiceAccount": "A String", # [Output Only] Default service account used by VMs running in this project.
+    "enabledFeatures": [ # Restricted features enabled for use on this project.
+      "A String",
+    ],
+    "commonInstanceMetadata": { # A metadata key/value entry. # Metadata key/value pairs available to all instances contained in this project. See Custom metadata for more information.
+      "items": [ # Array of key/value pairs. The total size of all keys and values must be less than 512 KB.
+        {
+          "value": "A String", # Value for the metadata entry. These are free-form strings, and only have meaning as interpreted by the image running in the instance. The only restriction placed on values is that their size must be less than or equal to 32768 bytes.
+          "key": "A String", # Key for the metadata entry. Keys must conform to the following regexp: [a-zA-Z0-9-_]+, and be less than 128 bytes in length. This is reflected as part of a URL in the metadata server. Additionally, to avoid ambiguity, keys must not conflict with any other metadata keys for the project.
+        },
+      ],
+      "kind": "compute#metadata", # [Output Only] Type of the resource. Always compute#metadata for metadata.
+      "fingerprint": "A String", # Specifies a fingerprint for this request, which is essentially a hash of the metadata's contents and used for optimistic locking. The fingerprint is initially generated by Compute Engine and changes after every request to modify or update metadata. You must always provide an up-to-date fingerprint hash in order to update or change metadata.
+    },
+    "quotas": [ # [Output Only] Quotas assigned to this project.
+      { # A quotas entry.
+        "usage": 3.14, # [Output Only] Current usage of this metric.
+        "metric": "A String", # [Output Only] Name of the quota metric.
+        "limit": 3.14, # [Output Only] Quota limit for this metric.
+      },
+    ],
+    "name": "A String", # The project ID. For example: my-example-project. Use the project ID to make requests to Compute Engine.
+    "usageExportLocation": { # The location in Cloud Storage and naming method of the daily usage report. Contains bucket_name and report_name prefix. # The naming prefix for daily usage reports and the Google Cloud Storage bucket where they are stored.
+      "bucketName": "A String", # The name of an existing bucket in Cloud Storage where the usage report object is stored. The Google Service Account is granted write access to this bucket. This can either be the bucket name by itself, such as example-bucket, or the bucket name with gs:// or https://storage.googleapis.com/ in front of it, such as gs://example-bucket.
+      "reportNamePrefix": "A String", # An optional prefix for the name of the usage report object stored in bucketName. If not supplied, defaults to usage. The report is stored as a CSV file named report_name_prefix_gce_YYYYMMDD.csv where YYYYMMDD is the day of the usage according to Pacific Time. If you supply a prefix, it should conform to Cloud Storage object naming conventions.
+    },
+    "xpnProjectStatus": "A String", # [Output Only] The role this project has in a Cross Project Network (XPN) configuration. Currently only HOST projects are differentiated.
+    "creationTimestamp": "A String", # [Output Only] Creation timestamp in RFC3339 text format.
+    "id": "A String", # [Output Only] The unique identifier for the resource. This identifier is defined by the server. This is not the project ID, and is just a unique ID used by Compute Engine to identify resources.
+    "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
+    "description": "A String", # An optional textual description of the resource.
+  }</pre>
+</div>
+
+<div class="method">
+    <code class="details" id="listXpnHosts">listXpnHosts(project, body)</code>
+  <pre>List all XPN host projects visible to the user in an organization.
+
+Args:
+  project: string, Project ID for this request. (required)
+  body: object, The request body. (required)
+    The object takes the form of:
+
+{
+    "organization": "A String", # Optional organization ID managed by Cloud Resource Manager, for which to list XPN host projects. If not specified, the organization will be inferred from the project.
+  }
+
+
+Returns:
+  An object of the form:
+
+    {
+    "nextPageToken": "A String", # [Output Only] This token allows you to get the next page of results for list requests. If the number of results is larger than maxResults, use the nextPageToken as a value for the query parameter pageToken in the next list request. Subsequent list requests will have their own nextPageToken to continue paging through the results.
+    "items": [ # [Output Only] A list of XPN host project URLs.
+      { # A Project resource. Projects can only be created in the Google Cloud Platform Console. Unless marked otherwise, values can only be modified in the console.
+        "kind": "compute#project", # [Output Only] Type of the resource. Always compute#project for projects.
+        "defaultServiceAccount": "A String", # [Output Only] Default service account used by VMs running in this project.
+        "enabledFeatures": [ # Restricted features enabled for use on this project.
+          "A String",
+        ],
+        "commonInstanceMetadata": { # A metadata key/value entry. # Metadata key/value pairs available to all instances contained in this project. See Custom metadata for more information.
+          "items": [ # Array of key/value pairs. The total size of all keys and values must be less than 512 KB.
+            {
+              "value": "A String", # Value for the metadata entry. These are free-form strings, and only have meaning as interpreted by the image running in the instance. The only restriction placed on values is that their size must be less than or equal to 32768 bytes.
+              "key": "A String", # Key for the metadata entry. Keys must conform to the following regexp: [a-zA-Z0-9-_]+, and be less than 128 bytes in length. This is reflected as part of a URL in the metadata server. Additionally, to avoid ambiguity, keys must not conflict with any other metadata keys for the project.
+            },
+          ],
+          "kind": "compute#metadata", # [Output Only] Type of the resource. Always compute#metadata for metadata.
+          "fingerprint": "A String", # Specifies a fingerprint for this request, which is essentially a hash of the metadata's contents and used for optimistic locking. The fingerprint is initially generated by Compute Engine and changes after every request to modify or update metadata. You must always provide an up-to-date fingerprint hash in order to update or change metadata.
+        },
+        "quotas": [ # [Output Only] Quotas assigned to this project.
+          { # A quotas entry.
+            "usage": 3.14, # [Output Only] Current usage of this metric.
+            "metric": "A String", # [Output Only] Name of the quota metric.
+            "limit": 3.14, # [Output Only] Quota limit for this metric.
+          },
+        ],
+        "name": "A String", # The project ID. For example: my-example-project. Use the project ID to make requests to Compute Engine.
+        "usageExportLocation": { # The location in Cloud Storage and naming method of the daily usage report. Contains bucket_name and report_name prefix. # The naming prefix for daily usage reports and the Google Cloud Storage bucket where they are stored.
+          "bucketName": "A String", # The name of an existing bucket in Cloud Storage where the usage report object is stored. The Google Service Account is granted write access to this bucket. This can either be the bucket name by itself, such as example-bucket, or the bucket name with gs:// or https://storage.googleapis.com/ in front of it, such as gs://example-bucket.
+          "reportNamePrefix": "A String", # An optional prefix for the name of the usage report object stored in bucketName. If not supplied, defaults to usage. The report is stored as a CSV file named report_name_prefix_gce_YYYYMMDD.csv where YYYYMMDD is the day of the usage according to Pacific Time. If you supply a prefix, it should conform to Cloud Storage object naming conventions.
+        },
+        "xpnProjectStatus": "A String", # [Output Only] The role this project has in a Cross Project Network (XPN) configuration. Currently only HOST projects are differentiated.
+        "creationTimestamp": "A String", # [Output Only] Creation timestamp in RFC3339 text format.
+        "id": "A String", # [Output Only] The unique identifier for the resource. This identifier is defined by the server. This is not the project ID, and is just a unique ID used by Compute Engine to identify resources.
+        "selfLink": "A String", # [Output Only] Server-defined URL for the resource.
+        "description": "A String", # An optional textual description of the resource.
+      },
+    ],
+    "kind": "compute#xpnHostList", # [Output Only] Type of resource. Always compute#xpnHostList for lists of XPN hosts.
+    "id": "A String", # [Output Only] The unique identifier for the resource. This identifier is defined by the server.
+    "selfLink": "A String", # [Output Only] Server-defined URL for this resource.
+  }</pre>
+</div>
+
+<div class="method">
     <code class="details" id="moveDisk">moveDisk(project, body)</code>
   <pre>Moves a persistent disk from one zone to another.
 
@@ -203,7 +316,7 @@
     },
     "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>
 
@@ -274,7 +387,7 @@
     },
     "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>
 
@@ -345,7 +458,7 @@
     },
     "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>
 
@@ -359,9 +472,9 @@
     The object takes the form of:
 
 { # The location in Cloud Storage and naming method of the daily usage report. Contains bucket_name and report_name prefix.
-    "bucketName": "A String", # The name of an existing bucket in Cloud Storage where the usage report object is stored. The Google Service Account is granted write access to this bucket. This can either be the bucket name by itself, such as example-bucket, or the bucket name with gs:// or https://storage.googleapis.com/ in front of it, such as gs://example-bucket.
-    "reportNamePrefix": "A String", # An optional prefix for the name of the usage report object stored in bucketName. If not supplied, defaults to usage. The report is stored as a CSV file named report_name_prefix_gce_YYYYMMDD.csv where YYYYMMDD is the day of the usage according to Pacific Time. If you supply a prefix, it should conform to Cloud Storage object naming conventions.
-  }
+  "bucketName": "A String", # The name of an existing bucket in Cloud Storage where the usage report object is stored. The Google Service Account is granted write access to this bucket. This can either be the bucket name by itself, such as example-bucket, or the bucket name with gs:// or https://storage.googleapis.com/ in front of it, such as gs://example-bucket.
+  "reportNamePrefix": "A String", # An optional prefix for the name of the usage report object stored in bucketName. If not supplied, defaults to usage. The report is stored as a CSV file named report_name_prefix_gce_YYYYMMDD.csv where YYYYMMDD is the day of the usage according to Pacific Time. If you supply a prefix, it should conform to Cloud Storage object naming conventions.
+}
 
 
 Returns:
@@ -410,7 +523,7 @@
     },
     "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>