Improve storage bucket acls (#131)

Improve storage bucket acls

plugins/modules/gcp_storage_bucket_access_control.py

@@ -120,6 +120,19 @@
     - This should not be set unless you know what you're doing.
     - This only alters the User Agent string for any API requests.
     type: str
+notes:
+- 'API Reference: U(https://cloud.google.com/storage/docs/json_api/v1/bucketAccessControls)'
+- 'Official Documentation: U(https://cloud.google.com/storage/docs/access-control/lists)'
+- for authentication, you can set service_account_file using the C(gcp_service_account_file)
+  env variable.
+- for authentication, you can set service_account_contents using the C(GCP_SERVICE_ACCOUNT_CONTENTS)
+  env variable.
+- For authentication, you can set service_account_email using the C(GCP_SERVICE_ACCOUNT_EMAIL)
+  env variable.
+- For authentication, you can set auth_kind using the C(GCP_AUTH_KIND) env variable.
+- For authentication, you can set scopes using the C(GCP_SCOPES) env variable.
+- Environment variables values will only be used if the playbook values are not set.
+- The I(service_account_email) and I(service_account_file) options are mutually exclusive.
 '''
 
 EXAMPLES = '''