Add BattleofTheBits connection for songs

Certain modules such as dumpstore.it and suck_a_dick.it originates from BattleofTheBits [1] [2]. Unfortunately it now asks to log in with an account to visit song pages. It seems some of them doesn't have reuploads on ModArchive so that's why I ask to include it as connection.

The list of sites currently allowed for connections have so far been ones for the purpose of information and/or archival rather than distribution. I feel like this would be better as a link in the wiki text on the song page, especially because BotB is login-gated now, so more information could be written about it that is otherwise difficult to access.