* Add missing preview features of Deployment and Deployment Statuses API
- Enable support for deployment status states in_progress and queued
- Add arguments production_environment and transient_environment to Repository.create_deployment()
- Add attributes production_environment and transient_environment to Deployment
- Use correct type in assertion for Deployment.payload
- Fix incorrect assertion for description in Deployment.create_status()
- Add arguments environment, environment_url, auto_inactive to Deployment.create_status()
- Add attribute environment_url to DeploymentStatus
Deployment, TimelineEvent{,Source} were missing mypy stubs, since they
were added after the mypy branch was started. Add them, and clean up two
spurious __future__ imports that are no longer required. Add mypy's
cache directory to .gitignore