mariadb-binlog should work between (almost) any release

We should ensure that one can use the MariaDB binlogs as a form of 'incremental backup' between 'any' release that support the same MariaDB SQL syntax.

Providing support for earlier releases is important if upgrading to a new major release fails and the customer has to go back to an earlier release. In this case the binary logs may be the only way to recover all data!

If binary format for row events is changed in a incompatible way, we should to enhance MariaDB to write the row events as normal SQL events or alternatively consider adding an option like '--remote-server=10.6' that would change the output from mariadb-binlog to match data expected by the given server version.

In buildbot we should add test to test for mariadb-binlog to send data from the current version to next and previous major versions.