Release Spanner 1.5.0

* Support STRUCT values in query parameters.
  * Add Fields#struct to create a Data object.
* Documentation updates.

Release Pub/Sub 0.31.0

* Switch Subscriber to use unary RPC calls for ack/modack.
* Reduce number of String objects that are garbage collected.
* Documentation updates.

Merge pull request googleapis#2114 from GoogleCloudPlatform/release-g…

…oogle-cloud-0.54.0

Release google-cloud-tasks 0.1.0

Release stackdriver 0.15.0

Release Firestore 0.21.1

* Fix bug where some DocumentReference/DocumentSnapshot actions
  were failing due to a bad object configuration.
* Updates to documentation and code examples.

Release google-cloud-debugger 0.32.0

Release google-cloud-bigquery 1.5.0

* Add Schema.load and Schema.dump to read/write a table schema from/to JSON file.
* Add support for the NUMERIC data type.
* Add documentation for enabling logging.

Release google-cloud-storage 1.12.0

* Support Cloud KMS keys / Customer-managed encryption keys (CMEK).

Release google-cloud 0.53.0

* Add Google Cloud Memorystore for Redis.