Stop using mox.stubs in heat
Stop using mox.stubs in heat

This patch stop using mox.stubs in test_wsgi. Now we ues mock
package in unit tests.
Implements:  blueprint mox-to-mock-conversion

Change-Id: If892379dfe7f8b54ae8fe01812249cf529904f45

noironetworks/heat,openstack/heat,noironetworks/heat,cwolferh/heat-scratch,openstack/heat,cwolferh/heat-scratch