23f13437dd deprecated the
purely volume or volume-snapshot related CLIs and python
API bindings during Kilo. python-cinderclient should be
used for the python API bindings now, and python-openstackclient
should be used for the CLI for those operations.
The alternate_service_type context manager is also removed
since it was only used for proxying through to the volume API
endpoint.
Since the proxy for creating volumes is removed, we have to
add python-cinderclient for testing the volume attachment
CLIs/APIs that are left intact.
Change-Id: I09a6501603667350f49b1b1fa130353a6d5272a2