Tenants API Tenant Tests Parity.

1. Added a tenant test.
2. Refactored identity fixtures.
3. Fixed reviewer comment - minor typo.
4. Fixed reviewer comment - change import of rand_name.
5. Renamed test_repo to cloudroast.
6. Fixed reviewer comment - fixed data clean up issues in test_tenants.
7. Refactored test_tenant/fixtures.
8. Rebased changes to fixe a merge faillure.
9. Fixed reviewer comment - removed teardown in test_tenants.
10. Flipped the order in assertEqual as per best practices.

Change-Id: I58d3eeb27582b169dde4ee4381f0c67f4cd66b25
Merge "Tenants API Tenant Tests Parity."