Merge pull request #340 from xwp/feature/wptests-user-password

Restore wptests MySQL user password to wptests per wp-tests-config.php
Merge pull request #339 from xwp/feature/phpunit-batcache-undefined-var

Fix undefined batcache variable during phpunit execution
Merge branch 'master' of https://github.com/Automattic/vip-quickstart into develop