[New Feature] Testing with molecule (in docker containers)

[lhoss]

Main motivation: reduce testing boilerplate and hacks..

Status

Here's my initial work (travis not yet updated to use molecule):
https://github.com/AnsibleShipyard/ansible-zookeeper/compare/master...teralytics:molecule_docker_tests?expand=1

PR: planned soon, after resolving tasks:

• fix ansible-lint issues (see fix ansible-lint warnings #59)
• test the actual testinfra tests
• cleanups

Howto

• Setup molecule: http://molecule.readthedocs.io/en/stable-1.17/#quick-start
• run it (in the project's root dir):

molecule test

and the 3 containers will be created, java,zookeeper deployed and will stop after the above ansible-lint warnings