Bossy boots

Today I implemented the boss attack and worked out some sound effects, which I might replace later. I also worked out how to get the boss graphic to align with the background, which has applications elsewhere in my game.

I've also redone the gp2x build a bit, it's a little faster now.

Tomorrow I aim to misbehave sort out the levels a fair bit, as the crypt and basement need work badly, and a few places need (temporary, at least) music.