Document how replication filters are evaluated

Our documentation suggests reading the MySQL manual to see how replication filters are evaluated:

The following variables are used on a replication slave to restrict replicated changes to specific databases and/or tables (see the MySQL manual for details on the semantics on how this works with statement-based and row-based replication):

https://mariadb.com/kb/en/library/dynamic-replication-variables/

I believe this is the MySQL manual page that it is referring to:

https://dev.mysql.com/doc/refman/5.5/en/replication-rules.html

Maybe the MariaDB documentation should have its own similar explanation of replication filters, so we don't need to rely on the MySQL manual.