Added unit tests for reddwarf.guestagent.pkg module.
Added tests for package install, remove and version
Changing the test runner of unittests to be run by testr instead of probocis/nose
Remove probocis reference from the dbaas test
Moved dbaas.py to reddwarf/tests/unittests
tracked by bug #1090139
Change-Id: Ia25fbe996d04d39e83edef0369de0e7fccce579e