3.0.1

added option for docker.io engine on ubuntu 16.04

Version 3.0

• Removed any kernel upgrading and related variables. Moved to a new role.
  See: https://github.com/locationlabs/ansible-role_docker-base
• Refactored testing.
• Ensure a few required packages are getting installed.

Version 2.2.1

• wait for Docker to actually be running before re-reading ansible docker facts.

Version 2.2

• Removed the upgrade fixes added in Version 2.1.
• No longer pass the "--force-confnew" flag to apt when installing the Docker package.
  This flag, added in 2.1.2, turned out to have some undesirable side effects.
• Role now manages the "/etc/default/docker" file. The config variable "docker_daemon_flags"
  controls what is passed to DOCKER_OPTS in that file.

Version 2.1.2

• Pass the "--force-confnew" flag to dpkg when installing the Docker package, to make sure configuration files are replaced even if they have been edited.

Version 2.1.1

• Stop the "docker" service before attempting a package upgrade, to prevent an intermittent
  upgrade failure.

Version 2.1

• Removed default Docker version; "docker_version" is now a required variable.

• Attempt to handle data volume loss when we update from pre-1.10 to post-1.10. See:

  moby/moby#20079

• Attempt to handle missing volume symlinks when we upgrade pre-1.9 data volumes to a post-1.9.x version.

• Add "docker_attempt_upgrade_fixes" configuration variable. This defaults to False; the upgrade fixes mentioned above won't be attempted unless it is set to True.

• Added automated tests in the "tests" directory - if you have Vagrant installed, they can be run by "cd tests ; ./run_tests.sh".