Following commits:
Change 608808
Change 604284
Use keystoneauth1.load.get_plugin_loader to load and discovery dynamically
without explicitly specifying V2 or V3 of keystone.
The argument of "--os-identity-api-version" is no longer required.
Change-Id: Idbd324d30489ae3c6a279e7147387fea81f39063
5fd8f1bbb1