shaders: rotational transformations enabled

Vertex shader is now a total bro. Step it up, fragment shader. You might think it's pointless to bother with shaders and graphics, this is a physics engine! I've said it before and I'll say it again: debugging. I'd rather not be plotting trajectories with gnuplot every time I run this thing. Especially considering how complex the scrips get when you have 3D. Therefore, investing time here will certainly please our investors in the long run, and our investors are not the kind of people you'd want to disappoint. You mess around and... erm... accidents could happen.