fix glew.h usages (lack thereof actually)

instead of using qt's builtin opengl bullshit, we're now using some
other extension loader. looks like it's just impossible otherwise, and
nobody has a clue on how to do it like that anyways.
bit of progress towards switching over to qt

still have a lot of sdl to strip out
fix glew vs sdl vs qt competing, don't call qopenglfunctions before init

(or at all, in the case of now)