Initial Oslo sync for Tempest.

This patch syncs cfg, iniparser, and setup from oslo.
Additionally, to avoid a name conflict tempest.openstack was
renamed tempest.clients.

Also, the duplicate copy of setup.py in tempest.common was removed
and all references to it were updated.

Change-Id: I6ed3a97e35ce73b820f7a436214480051ed6528f
Merge "Initial Oslo sync for Tempest."