Add A use for Dr.Acula

[Glamurio]

Just as an update to this, turns out the situation is a bit of a mess because of the way the code of Dr. Acula is handled. There's a big code refactoring happening that reworks how a lot of the AI is handled in the game, and bats fall under this category as well.

I've got a working code right now, but I'm not going to be publishing it until I've finished migrating some of the bat code to the new format, so that's going to take a bit of time. In the meantime, enjoy the new sprite (which is really just a recolored zombee ).