Remove a bunch of things we promised to remove in 2H 2017

Change-Id: I060559fe13e354fe87551cd9dd82774bddb54640

Author: Dean Troyer

openstackclient/api/auth.py

@@ -15,8 +15,8 @@
 
 import mock
 import openstack
+from osc_lib import exceptions
 
-from openstackclient.common import exceptions
 from openstackclient.network import common
 from openstackclient.tests.unit import utils