Use cinder.conf for auth_token configs.

Updates lib/cinder so that we use the application config file (cinder.conf)
instead of the Cinder api-paste.ini config file.

Related-Bug #1240753

Change-Id: I6636d33ee522757145ac97fc354324a8b9379700
Merge "Use cinder.conf for auth_token configs." into stable/havana