The code has been moved into openstacksdk. Make os-client-config a
thin wrapper around that code.
The legacy client code needs to stay, as it was removed in openstacksdk.
We also have to plumb os_client_config.defaults and
os_client_config.cloud_region.CloudRegion in so that users get the
os-client-config versions from the openstacksdk methods that return the
relevant objects.
Support for per-service region_name has been dropped. This was never
used anywhere and was added for compatibility with openstacksdk Profile
objects. Since Profile objects are no more, we can remove it. It never
made any sense.
Change-Id: I7180e20aa675c0ccbe3718493a6eff2be7e1b8b6
5c2eae8f82