Remove connect in fixture

The mysql fixture was creating new backends and connections every time
it was instantiated. This was causing instability in the test. The
fixture has been pared down to stateless items. Connections in setup
and teardown are now explicit. This precvents mysql from blocking
database table schema and table deletes.
Fix DataTable so it points to the target and not the source

This test was pointing at the source and not the target when writing.
Attempt to fix issues in mysql and postgres

This test is still failing in its current state
Fixes to support travis-ci