Sync config fixture object from oslo.incubator

Specify the config file directly otherwise we end up with a lot of new
dependencies.

Change-Id: Id39f5c039d5d0d68ab6e4008a1212868396eda3e
Tests should use identity_uri by default

auth_token middleware tests should use the identity_uri variable by
default now that we have deprecated the auth fragments.

Blueprint: identity-uri
Change-Id: I897939498b411086d06b3ed16060cbc0e482e519
Merge "Sync config fixture object from oslo.incubator"
Merge "Tests should use identity_uri by default"