Toon Shader sample

[AVinitzca]

• Added a sample that showcases toon shading techniques.
• The first one uses a color gradient, passed to the shader as four colors and ranges for each one.
• The second technique uses a Look Up Texture to know which color to paint fragments, depending on the result of the lighting equation. It uses the result of the lighting equation as a one-dimension texture coordinate, then it samples the LUT in that coordinate and gets a resulting color.
• Also added EffectParameter handling for Vector3 modifiers.