snapmerge: disable warnings (for now)

For the rercord:
http://www.murga-linux.com/puppy/viewtopic.php?p=786714#786714
http://www.murga-linux.com/puppy/viewtopic.php?p=786871#786871
http://www.murga-linux.com/puppy/viewtopic.php?p=787027#787027