os x support
Merge branch 'master' into osx

Conflicts:
	main.c
Merge branch 'master' into osx

Conflicts:
	Makefile
	main.c
rx, ry in radians
signs
basic fog
world data in a buffer texture
Block struct
sky color, random world
render multiple chunks
Merge branch 'master' into osx

Conflicts:
	Makefile
	fragment.glsl
	main.c
	vertex.glsl
merge fixes
simplex noise ftw
.gitignore
hash map model, render exposed blocks only
parameters
MAP_FOR_EACH macro
desert bottom
render exposed faces only, no more instanced draw
simplified