Most of the changes revolves around using MySQL rather than MariaDB,
plus enabling the addon repos on public-yum.oracle.com.
The patch just touch the areas where there is a divergence between the
Fedora and Oracle distributions and in all other cases the is_fedora
will result in the correct decision to be made and left as is.
Collapsed the is_suse and is_oraclelinux into a single check in
configure_database_mysql and cleanup_database_mysql
Added Oracle Linux to MAINTAINERS.rst
Rather than duplicating most of the Redhat version check code, added
a check in the block to do the determination if it is Oracle Linux
Change-Id: I5f1f15106329eec67aa008b17847fa44863f243f