Release v1.6.0 (#324)

* Update version and changelog for v1.6.0
* Update docs
diff --git a/docs/dyn/cloudbuild_v1.projects.triggers.html b/docs/dyn/cloudbuild_v1.projects.triggers.html
index 95aecd5..bf98749 100644
--- a/docs/dyn/cloudbuild_v1.projects.triggers.html
+++ b/docs/dyn/cloudbuild_v1.projects.triggers.html
@@ -129,6 +129,9 @@
       "status": "A String", # Status of the build.
           # @OutputOnly
       "finishTime": "A String", # Time at which execution of the build was finished.
+          #
+          # The difference between finish_time and start_time is the duration of the
+          # build's execution.
           # @OutputOnly
       "timeout": "A String", # Amount of time that this build should be allowed to run, to second
           # granularity. If this amount of time elapses, work on the build will cease
@@ -156,7 +159,7 @@
           "A String",
         ],
       },
-      "createTime": "A String", # Time at which the build was created.
+      "createTime": "A String", # Time at which the request to create the build was received.
           # @OutputOnly
       "id": "A String", # Unique identifier of the build.
           # @OutputOnly
@@ -185,6 +188,9 @@
           "commitSha": "A String", # Explicit commit SHA to build.
         },
       },
+      "buildTriggerId": "A String", # The ID of the BuildTrigger that triggered this build, if it was
+          # triggered automatically.
+          # @OutputOnly
       "steps": [ # Describes the operations to be performed on the workspace.
         { # BuildStep describes a step to perform in the build pipeline.
           "waitFor": [ # The ID(s) of the step(s) that this build step depends on.
@@ -196,10 +202,9 @@
           ],
           "name": "A String", # The name of the container image that will run this particular build step.
               #
-              # If the image is already available in the host's
-              # Docker daemon's cache, it will be run directly. If not, the host will
-              # attempt to pull the image first, using the builder service account's
-              # credentials if necessary.
+              # If the image is already available in the host's Docker daemon's cache, it
+              # will be run directly. If not, the host will attempt to pull the image
+              # first, using the builder service account's credentials if necessary.
               #
               # The Docker daemon's cache will already have the latest versions of all of
               # the officially supported build steps
@@ -283,8 +288,7 @@
       "images": [ # A list of images to be pushed upon the successful completion of all build
           # steps.
           #
-          # The images will be pushed using the builder
-          # service account's credentials.
+          # The images will be pushed using the builder service account's credentials.
           #
           # The digests of the pushed images will be stored in the Build resource's
           # results field.
@@ -355,6 +359,9 @@
         "status": "A String", # Status of the build.
             # @OutputOnly
         "finishTime": "A String", # Time at which execution of the build was finished.
+            #
+            # The difference between finish_time and start_time is the duration of the
+            # build's execution.
             # @OutputOnly
         "timeout": "A String", # Amount of time that this build should be allowed to run, to second
             # granularity. If this amount of time elapses, work on the build will cease
@@ -382,7 +389,7 @@
             "A String",
           ],
         },
-        "createTime": "A String", # Time at which the build was created.
+        "createTime": "A String", # Time at which the request to create the build was received.
             # @OutputOnly
         "id": "A String", # Unique identifier of the build.
             # @OutputOnly
@@ -411,6 +418,9 @@
             "commitSha": "A String", # Explicit commit SHA to build.
           },
         },
+        "buildTriggerId": "A String", # The ID of the BuildTrigger that triggered this build, if it was
+            # triggered automatically.
+            # @OutputOnly
         "steps": [ # Describes the operations to be performed on the workspace.
           { # BuildStep describes a step to perform in the build pipeline.
             "waitFor": [ # The ID(s) of the step(s) that this build step depends on.
@@ -422,10 +432,9 @@
             ],
             "name": "A String", # The name of the container image that will run this particular build step.
                 #
-                # If the image is already available in the host's
-                # Docker daemon's cache, it will be run directly. If not, the host will
-                # attempt to pull the image first, using the builder service account's
-                # credentials if necessary.
+                # If the image is already available in the host's Docker daemon's cache, it
+                # will be run directly. If not, the host will attempt to pull the image
+                # first, using the builder service account's credentials if necessary.
                 #
                 # The Docker daemon's cache will already have the latest versions of all of
                 # the officially supported build steps
@@ -509,8 +518,7 @@
         "images": [ # A list of images to be pushed upon the successful completion of all build
             # steps.
             #
-            # The images will be pushed using the builder
-            # service account's credentials.
+            # The images will be pushed using the builder service account's credentials.
             #
             # The digests of the pushed images will be stored in the Build resource's
             # results field.
@@ -620,6 +628,9 @@
         "status": "A String", # Status of the build.
             # @OutputOnly
         "finishTime": "A String", # Time at which execution of the build was finished.
+            #
+            # The difference between finish_time and start_time is the duration of the
+            # build's execution.
             # @OutputOnly
         "timeout": "A String", # Amount of time that this build should be allowed to run, to second
             # granularity. If this amount of time elapses, work on the build will cease
@@ -647,7 +658,7 @@
             "A String",
           ],
         },
-        "createTime": "A String", # Time at which the build was created.
+        "createTime": "A String", # Time at which the request to create the build was received.
             # @OutputOnly
         "id": "A String", # Unique identifier of the build.
             # @OutputOnly
@@ -676,6 +687,9 @@
             "commitSha": "A String", # Explicit commit SHA to build.
           },
         },
+        "buildTriggerId": "A String", # The ID of the BuildTrigger that triggered this build, if it was
+            # triggered automatically.
+            # @OutputOnly
         "steps": [ # Describes the operations to be performed on the workspace.
           { # BuildStep describes a step to perform in the build pipeline.
             "waitFor": [ # The ID(s) of the step(s) that this build step depends on.
@@ -687,10 +701,9 @@
             ],
             "name": "A String", # The name of the container image that will run this particular build step.
                 #
-                # If the image is already available in the host's
-                # Docker daemon's cache, it will be run directly. If not, the host will
-                # attempt to pull the image first, using the builder service account's
-                # credentials if necessary.
+                # If the image is already available in the host's Docker daemon's cache, it
+                # will be run directly. If not, the host will attempt to pull the image
+                # first, using the builder service account's credentials if necessary.
                 #
                 # The Docker daemon's cache will already have the latest versions of all of
                 # the officially supported build steps
@@ -774,8 +787,7 @@
         "images": [ # A list of images to be pushed upon the successful completion of all build
             # steps.
             #
-            # The images will be pushed using the builder
-            # service account's credentials.
+            # The images will be pushed using the builder service account's credentials.
             #
             # The digests of the pushed images will be stored in the Build resource's
             # results field.
@@ -857,6 +869,9 @@
             "status": "A String", # Status of the build.
                 # @OutputOnly
             "finishTime": "A String", # Time at which execution of the build was finished.
+                #
+                # The difference between finish_time and start_time is the duration of the
+                # build's execution.
                 # @OutputOnly
             "timeout": "A String", # Amount of time that this build should be allowed to run, to second
                 # granularity. If this amount of time elapses, work on the build will cease
@@ -884,7 +899,7 @@
                 "A String",
               ],
             },
-            "createTime": "A String", # Time at which the build was created.
+            "createTime": "A String", # Time at which the request to create the build was received.
                 # @OutputOnly
             "id": "A String", # Unique identifier of the build.
                 # @OutputOnly
@@ -913,6 +928,9 @@
                 "commitSha": "A String", # Explicit commit SHA to build.
               },
             },
+            "buildTriggerId": "A String", # The ID of the BuildTrigger that triggered this build, if it was
+                # triggered automatically.
+                # @OutputOnly
             "steps": [ # Describes the operations to be performed on the workspace.
               { # BuildStep describes a step to perform in the build pipeline.
                 "waitFor": [ # The ID(s) of the step(s) that this build step depends on.
@@ -924,10 +942,9 @@
                 ],
                 "name": "A String", # The name of the container image that will run this particular build step.
                     #
-                    # If the image is already available in the host's
-                    # Docker daemon's cache, it will be run directly. If not, the host will
-                    # attempt to pull the image first, using the builder service account's
-                    # credentials if necessary.
+                    # If the image is already available in the host's Docker daemon's cache, it
+                    # will be run directly. If not, the host will attempt to pull the image
+                    # first, using the builder service account's credentials if necessary.
                     #
                     # The Docker daemon's cache will already have the latest versions of all of
                     # the officially supported build steps
@@ -1011,8 +1028,7 @@
             "images": [ # A list of images to be pushed upon the successful completion of all build
                 # steps.
                 #
-                # The images will be pushed using the builder
-                # service account's credentials.
+                # The images will be pushed using the builder service account's credentials.
                 #
                 # The digests of the pushed images will be stored in the Build resource's
                 # results field.
@@ -1090,6 +1106,9 @@
       "status": "A String", # Status of the build.
           # @OutputOnly
       "finishTime": "A String", # Time at which execution of the build was finished.
+          #
+          # The difference between finish_time and start_time is the duration of the
+          # build's execution.
           # @OutputOnly
       "timeout": "A String", # Amount of time that this build should be allowed to run, to second
           # granularity. If this amount of time elapses, work on the build will cease
@@ -1117,7 +1136,7 @@
           "A String",
         ],
       },
-      "createTime": "A String", # Time at which the build was created.
+      "createTime": "A String", # Time at which the request to create the build was received.
           # @OutputOnly
       "id": "A String", # Unique identifier of the build.
           # @OutputOnly
@@ -1146,6 +1165,9 @@
           "commitSha": "A String", # Explicit commit SHA to build.
         },
       },
+      "buildTriggerId": "A String", # The ID of the BuildTrigger that triggered this build, if it was
+          # triggered automatically.
+          # @OutputOnly
       "steps": [ # Describes the operations to be performed on the workspace.
         { # BuildStep describes a step to perform in the build pipeline.
           "waitFor": [ # The ID(s) of the step(s) that this build step depends on.
@@ -1157,10 +1179,9 @@
           ],
           "name": "A String", # The name of the container image that will run this particular build step.
               #
-              # If the image is already available in the host's
-              # Docker daemon's cache, it will be run directly. If not, the host will
-              # attempt to pull the image first, using the builder service account's
-              # credentials if necessary.
+              # If the image is already available in the host's Docker daemon's cache, it
+              # will be run directly. If not, the host will attempt to pull the image
+              # first, using the builder service account's credentials if necessary.
               #
               # The Docker daemon's cache will already have the latest versions of all of
               # the officially supported build steps
@@ -1244,8 +1265,7 @@
       "images": [ # A list of images to be pushed upon the successful completion of all build
           # steps.
           #
-          # The images will be pushed using the builder
-          # service account's credentials.
+          # The images will be pushed using the builder service account's credentials.
           #
           # The digests of the pushed images will be stored in the Build resource's
           # results field.
@@ -1316,6 +1336,9 @@
         "status": "A String", # Status of the build.
             # @OutputOnly
         "finishTime": "A String", # Time at which execution of the build was finished.
+            #
+            # The difference between finish_time and start_time is the duration of the
+            # build's execution.
             # @OutputOnly
         "timeout": "A String", # Amount of time that this build should be allowed to run, to second
             # granularity. If this amount of time elapses, work on the build will cease
@@ -1343,7 +1366,7 @@
             "A String",
           ],
         },
-        "createTime": "A String", # Time at which the build was created.
+        "createTime": "A String", # Time at which the request to create the build was received.
             # @OutputOnly
         "id": "A String", # Unique identifier of the build.
             # @OutputOnly
@@ -1372,6 +1395,9 @@
             "commitSha": "A String", # Explicit commit SHA to build.
           },
         },
+        "buildTriggerId": "A String", # The ID of the BuildTrigger that triggered this build, if it was
+            # triggered automatically.
+            # @OutputOnly
         "steps": [ # Describes the operations to be performed on the workspace.
           { # BuildStep describes a step to perform in the build pipeline.
             "waitFor": [ # The ID(s) of the step(s) that this build step depends on.
@@ -1383,10 +1409,9 @@
             ],
             "name": "A String", # The name of the container image that will run this particular build step.
                 #
-                # If the image is already available in the host's
-                # Docker daemon's cache, it will be run directly. If not, the host will
-                # attempt to pull the image first, using the builder service account's
-                # credentials if necessary.
+                # If the image is already available in the host's Docker daemon's cache, it
+                # will be run directly. If not, the host will attempt to pull the image
+                # first, using the builder service account's credentials if necessary.
                 #
                 # The Docker daemon's cache will already have the latest versions of all of
                 # the officially supported build steps
@@ -1470,8 +1495,7 @@
         "images": [ # A list of images to be pushed upon the successful completion of all build
             # steps.
             #
-            # The images will be pushed using the builder
-            # service account's credentials.
+            # The images will be pushed using the builder service account's credentials.
             #
             # The digests of the pushed images will be stored in the Build resource's
             # results field.