We need the ability to run database tests on mysql in addition to sqlite

Unit tests in projects such as nova which work on the database only work with sqlite databases. In most cases this isn't an issue, but items like migrations actually are different depending on the different databases used. We need the ability to have these tests work with mysql (and later postgresql and others) as well.

The proposed mechanism is to assume there will be a mysql database setup with a predefined name / user / password that should be unique to us, like 'openstack_novaunittests'. If we can successfully connect to that database we'll run mysql tests. If we run into any issue in connecting to the database, we'll skip the tests. There will also be a test to check that skipping works by passing bad credentials to it.