mod_http_muc_log: Tweak style towards the "modern" Also accidentally converted the hand-minified CSS to SCSS for easier editing. This gets rid of the <q> element because it makes browsers (at least Firefox) add annoying quotes to any text copied out of them, interfering with opening non-linkified URLs. That could have been considered a sort of security mechanism, but convenience trumps security!

This module writes out a traceback to `traceback.txt` in Prosodys data
directory (see `prosodyctl about`) when the signal `SIGUSR1` is
received. This is useful when debugging seemingly frozen instances in
case it is stuck in Lua code.