2.22rc1

• Added docker-machine support
• Pass etc_hosts through to docker_container module
• Fixed dependency gem for rubocop
• Use selinux shim library for testing
• Bumbed multiple requirements
• Add ansible_args support back to converge command
• Fix Deprecations
• Support pruning of docker volumes in 'destroy' phase
• CI Fixes for ansible 2.8
• Other minor fixes