Remove ATOM responses for list versions and get version details.

Once https://review.openstack.org/#/c/110768/ merges,
the JSON and XML list versions responses will update.
Also, other clean-up (formatting, future tense)

Change-Id: If9248bdd9e73ccc7ac7871aa8981925eb5a889d4
Closes-Bug: #1338120
Merge branch 'master' of https://github.com/raildo/identity-api