Use versions_client, versions from tempest-lib

Below files have been migrated to tempest-lib-

 * versions_client.py: I41ec60e12a155ee80f3a1825405bdd6e1ec82425
 * versions.py: I41ec60e12a155ee80f3a1825405bdd6e1ec82425

Now Tempest-lib provides those as stable interfaces. So Tempest should
start using those from lib and remove its own copy.

Change-Id: I963bd08f28d990b4ef31cdd65601074349e8c509
3 files changed