Fixed magnitude calculation

Cleaned up world.c and physics.c
Merge branch 'master' of https://github.com/aacoppa/flaming-flamingos

Conflicts:
	src/matrix/vector.c
	src/world.c
Fixed drawing error in spheres

Need to draw_sphere at 0, 0, 0 and then
translate based on x,y,z not draw sphere at
x, y, z when we get our original matrix