Updated openstack/openstack
Project: openstack/nova  9c30669f43c9c35d0dbcfde87e121d42c65efeae

simplify database fixture to the features we use

The Database fixture has existed for a long time, and has a large
amount of vestigial code that is no longer usable as it's masked by
other test setup. For instance, the conf fixture always sets the db
connection string to in memory db.

Simplify what the Database fixture is doing to just the inmemory
schema caching and reconstruction. Also provide a test case
demonstrating that this both sets up the db correctly, as well as
resets it after we've made changes.

Change-Id: Idc9b587c705c1c1ab4e1173ad1e8e244037284d7