now with lighting!

I've been working on lighting effects; here you can see some of the fruits of that labor. (light fruit?) there is an issue with the red lasers in this first dungeon, in that they don't light things up the way you think they should. this will be fixed.

I'm not sure what took longer: coding the logic (and subtractive blending) for lighting, or updating all the underground maps to tell the game "hey! I'm a dark place!"