Updated openstack/openstack
Project: openstack/heat  0b25affb9cd8680c49b42f0b12d9521e6955e8f5

Use the new oslotest library

There is a new support library extracted from oslo incubator: the patch
starts using it and removes deprecated modules.

Change-Id: I3839af20613ff6ab905dddb8fc4be65654c6e949