Updated openstack/openstack
Project: openstack/nova  b541ecc36bd5b8427b5f3b3cbdf4658216a2a0e2
null
Change assertTrue(isinstance()) by optimal assert

Some of tests use different method of assertTrue(isinstance(A, B)) or
assertEqual(type(A), B). The correct way is to use assertIsInstance(A,
B) provided by testtools.

Change-Id: I4a5413f9d90d2e581044885a440a46bf3d76598f
Closes-Bug: #1268480