added first GLSL code, moved some graphics functions around, and adjusted some existing shader parser code

clean up pixel unpack buffer for dynamic textures, and add some more error handling code for other GL functions

update graphics subsystem code to add mipmap support and also add initial GL texture stuff and helper functions

the cleanup code I was going to add isn't necessary in this function, so just make gl_platform_init function return false

fixed some more alignment issues for SSE usage (maybe I should cut donw the size of the align function)