Identity tests v3

* Split identity/fakes.py for v2_0 and v3
* Split identity/test_identity.py for v2_0 and v3
* Add project, role, service, user v3 tests
* Fix issues in commands with enable/disable

Change-Id: Idcf81273f5eeb9f7d40a81b4ab31bb88d677193d
Merge branch 'test-clientmanager' into dt-test
Merge branch 'test-identity-v3' into dt-test