Added color method to Renderer. All demos use Graphics when possible.
Clean up if statements.
Fix bugs in shaders. For specular calculations NdotL must be greater than 0.000001 because pow really doesn't like 0 for the value to raise to the power of. It's quirky behavior. The vertex shader blinn_phong_specular_directional.vsh was still referencing the halfVector as part of the light. The spot light shaders also had issues when pow had a 0 for the value to raise to the power of. Both specular directional shaders were recalculating eyeLightDir.
Added a demo for vertex lit shaders.