Level compression

For the Doom level I made a small ASCII compressor to reduce the size of the level data. It's now at 9k, or 50 lines for floors+walls. That should make the overall source fairly readable and I'll probably come in at less than 250 lines of code for the total level once I've added ceiling, doors, elevators and some super-dumb bots. Not to foul for a Doom 1 prototype.