Rendering shadows

Another major step is done, rendering shadow volumes of 3d objects:

The shadow looks beautiful, I have to say, stencil shadows are great. Also Rune does not appear to be floating over the ground anymore in this scene.

WME has some more shadow techniques (looks like it got real time shadow mapping, if the graphics card supports it), but they don’t seem to be too relevant, so it might be better to postpone their porting until a later point.

One thing which is bugging me is the fact that lightning does still not give the same results everywhere compared to WME. But I am going to accept this for now. Now is the time to add some more missing stuff and cleanup the existing code.