Force Github plugins to update

It doesn't really matter if there's already a repo present,
we want to update the github plugins to whatever is the
latest on Github.

Fixes #278
Fix undefined batcache variable during phpunit execution
Restore wptests MySQL user password to wptests per wp-tests-config.php
Merge branch 'feature/wptests-user-password' into develop
Merge branch 'feature/phpunit-batcache-undefined-var' into develop