Removed some redundant code from 012_checker_sphere.
013_spiral_sphere updated to be compatible with MacOS X.
016_cartoon_torus updated to be compatible with MacOS X.

gl.LineWidth(4.0f) does not work as in the core 3.2 profile.
016_noise_torus updated to be compatible with MacOS X.
016_metallic_torus updated to be compatible with MacOS X.