Update variables documentation
Move vars out of ansible_ variable scope
Add integration tests
Update to latest stable maven version 3.2.3
ansible-maven 0.4.0: Move vars out of ansible_ variable scope
Merge branch 'release/0.4.0'

* release/0.4.0:
  ansible-maven 0.4.0: Move vars out of ansible_ variable scope
  Update to latest stable maven version 3.2.3
  Add integration tests
  Move vars out of ansible_ variable scope
  Update variables documentation