Add features to light

Light changes

• Change the spotlight cone control to be based on degrees of the cone and portion of the cone size for edge (e.g. 0.2 is 20%)
  • This is a change in behavior - please update the values in previous projects using spotlight.
• Add specular light control to 3DObject lights (generally use sparingly for a decent look)
• Add Set View Position to be used for specular calculation (set to the 3D camera location)
• Add distance attenuation, using the traditional formula: att = att / (1.0*attConstant + distance * attLinear + distance * distance * attSquare)

See updated example project to test it out.