
Add ability to use python-pymysql library as backend for MySQL connections. Update acceptance tests to use pyMySQL. Docs: https://wiki.openstack.org/wiki/PyMySQL_evaluation The same implementation as it's done for keystone: https://review.openstack.org/#/c/242134/ Change-Id: Ibc5b9717d681d9a090777d4fe64b906c3c07ec5d