General Availability release. Announced general availability of Google Cloud Internet of Things (IoT) Core

## Feature **General Availability release.** Announced general availability of Google Cloud Internet of Things (IoT) Core. ## Feature Device registries can now have multiple associated Cloud Pub/Sub topics. For more information, see [Creating a device registry with multiple Pub/Sub topics](https://cloud.google.com/iot/docs/how-tos/devices#creating%5Fa%5Fdevice%5Fregistry%5Fwith%5Fmultiple%5Fpubsub%5Ftopics). ## Feature Pricing examples have been added to the [Pricing](https://cloud.google.com/iot/pricing) page for MQTT and HTTP clients. ## Feature The Cloud IoT Core gcloud commands are now at the [General Availability release level](https://cloud.google.com/sdk/gcloud/#release%5Flevels). The `beta` label is no longer required. ## Feature An [interactive tutorial](https://console.cloud.google.com/start?tutorial=iot%5Fcore%5Fquickstart) version of the Quickstart is available. ## Feature A sample for [how to send large configuration updates to a device](https://cloud.google.com/iot/docs/samples/device-manager-samples#send%5Fa%5Flarge%5Ffile%5Fto%5Fa%5Fdevice) is available. ## Feature Samples have been added for the following languages: C#, Go, and Ruby. ## Feature A Cloud IoT Core [discussion group](https://cloud.google.com/iot/docs/getting-support) is available. ## Change A new IAM role enables publishing to Cloud Pub/Sub. The global Cloud IoT Core service account is no longer used. For details, see [Troubleshooting](https://cloud.google.com/iot/docs/troubleshooting#im%5Fnot%5Freceiving%5Ftelemetry%5Fdata%5Fon%5Fcloud%5Fpubsub). ## Change The [API documentation](https://cloud.google.com/iot/docs/reference/rest/) has been restructured to differentiate between the two sets of resources in the Cloud IoT Core API: [cloudiot](https://cloud.google.com/iot/docs/reference/cloudiot/rest/) and [cloudiotdevice](https://cloud.google.com/iot/docs/reference/cloudiotdevice/rest/). ## Deprecate Version v1beta1 of the `projects.locations.registries.devices` API resource is deprecated.