Tenants API Behaviors:

1. Added tenants-api behaviors.
2. Refactored methods as per Role Tests Parity requirements.
3. Fixed serialization/deserialization issues to use reponse entity.
4. Renamed TenantClientBehavior to TenantsBehaviors
5. Raised exceptions when two or more users (roles or tenants) have the same name.

Change-Id: I00ad1cf7948ec626737a128871532464b86372ad
Added devstack environment reference config file

Change-Id: I39d34cea28293187665984fbc69117ee8859cf1d
Extensions API

    1. Added an extensions-api package to Identity.
    2. Moved Identity base and constant models to a common package.
    2. Added extensions-api responses model and client.
    3. Added a data folder for extensions-api tests.
    4. Tested extensions-api extension responses model and client.
    5. Fixed pep8 issues as per reviewer comments.
    6. Cherry-pick commit: 9c3806200a310d75f2643cdb57631a608c85a9ef.
    7. Added extensions-api admin parameter to extensions-api client.
    8. Added and tested list roles to extensions-api client.
    9. Made a small fix (import of Roles).
    10. Renamed sections and properties in Identity config.py.
    11. Renamed client to ExtensionsAPI_Client for consistency.
    12. Fixed all reviewer comments.
    13. Added a create role functionality to extensions-api client.
    14. Added create role test and refactored extensions-api client test.
    15. Added and tested delete role functionality to extensions-api client.
    16. Fixed reviewer comments - line continuation issues.
    17. Fixed reviewer comments - refactored extensions-api client and its test.
    18. Removed a section and property (extensions-api-admin) from Identity config.py.
    19. Added an admin extensions class to the constants model, to use it across API clients.
    20. Refactored extensions-api client and its test.
    21. Rebased changes and uploaded a new patchset.

Change-Id: I4f0691b5dfd2302c3414b3c8d4b881b1624063e6
Tenants API Client - User Tests Parity.

1. Refactored tenant responses model - obj_to_json method.
2. Refactored tenant client - create user for a tenant method.
3. Refactored tenant and client tests.

Change-Id: Ied4929f5387e56a33c7fbfd9e4a493c0e2442b78
Merge "Extensions API"
Merge "Added devstack environment reference config file"
Allow for url override for Compute

* Adds a config value for the base Compute url

Change-Id: Ifca379796f26dfb8a25810a0b8c323b1fcf86743
Merge "Tenants API Behaviors:"
Merge "Tenants API Client - User Tests Parity."
Merge "Allow for url override for Compute"