[fedora-d&i] [FBR] Adjust #fedora-diversity fedmsg IRC bot topics

Hi, the attached patch makes a small change to ircbot.py to change the #fedora-diversity IRC bot to only listen for new Pagure tickets, pull requests, and comments. This helps reduce the noise in the IRC channel and hopefully makes the bot more useful for the team. Let me know if anyone has feedback on this patch. -- Cheers, Justin W. Flory jflory7(a)gmail.com