There were two code paths that did the same thing, and while
the code paths did the same thing, one of them supported region_name
and the other one did not.
Moving all this functionality into a single function to prevent this
from happening in the future.
- Re-factored make_client and create_connection.
- Remove now unused sdk.py.
- Renamed test_sdk to test_plugin.
Change-Id: Ibb477290c90e9af51be3537d11cf5142041db37f
f598fd23e1