tests remove test_heatclient unnecessary mock

The mock_ks_v3_client.users mock is not needed in this test.

Change-Id: I9f61da1c7203d7b42177ce78491a3963023318f9
Restructure Rackspace resources

During doc generation, resources have their own templates and need
to be separate from non-resource modules.  This removes the ``heat``
``engine`` and ``plugins`` folders and moves all resources into a
``resources`` folder, effectively separating the custom Rackspace
Client from custom Rackspace resources.

Partial-Bug: #1271226
Change-Id: Idbdc8400d30e2e745a2dc1b2d2fa1b7cff50d57b
Rename rackspace.rst to contrib.rst

Partial-Bug: #1271226
Change-Id: I1b5f848ef7f8da645ea57a0a30e7f9b86a4c866b
Merge "tests remove test_heatclient unnecessary mock"
Merge "Rename rackspace.rst to contrib.rst"
Merge "Restructure Rackspace resources"