He was one of the first openly gay men in metal. Now, after losing everything in a house fire, Faith No More's Roddy Bottum is bankrolling an opera featuring crystal-meth arias and interspecies duetsIn a top-floor flat overlooking Arthur's Seat in Edinburgh, Roddy Bottum is talking me through his fringe show Sasquatch: The Opera. Bottum is the keyboard player in Faith No More, whose twisted take on hard rock propelle…