filter for ejabberd messages using blacklists

 The 'mod_pottymouth' ejabberd module aims to fill the void left by 'mod_shit'
 which has disappeared from the net. It allows individual whole words of a
 message to be filtered against a blacklist. It allows multiple blacklists
 sharded by language. To make use of this module the client must add the
 xml:lang attribute to the message xml.