Expand MariaDB support documentation
Expand MariaDB support documentation

Use the right order, fix minor syntax issues, and add section
detailing how to enable SSL support.

Change-Id: I6e30707f30ea3f03ce3beddb29aef0a5527b9cf6

openstack-packages/delorean,openstack-packages/delorean,openstack-packages/DLRN,openstack-packages/DLRN