This untangles some of the gigantic kitchen sink headers
in an attempt to split things into smaller files.
Also don't include gl.h, glext.h, windows.h,
and other such nonsense *everywhere*.
Lots of cleanups on the way too. More dead/unused code removal.
Remove incrFlag(), decrFlag() Lua functions.
This repairs pixel/vertex shader code that was seemingly
experimented with during testing, but it was never used and no
shaders ever made it to the data files.
- BBGE_BUILD_SHADERS defined
- Blur enabled in config
- Entering a "warplocalnode"-Node while taking damage
These conditions caused it to enable shader related code while taking the
screenshot for the warp transition, that caused a crash because the shader-
related gl*() function pointers were not initialzed, because the current
code never loads any shaders.
