As keystoneclient and other services rely more on keystoneauth we should
assume that keystoneauth is our base auth library, not keystoneclient
and start to default to the objects provided from there. This will make
it easier to remove these objects when the time comes.
For the session independant parts of keystoneclient we should use the
exception names as provided by keystoneauth instead of the aliases in
keystoneclient.
Change-Id: Ic513046f8398a76c244e145d6cc3117cdf6bb4cd
5b91fedd65