Support for multiple lights in shaders.
User controlled light counts and types using defines
Merge branch 'next' of https://github.com/seanpaultaylor/GamePlay into next

Conflicts:
	gameplay/res/shaders/colored.frag
	gameplay/res/shaders/lighting.frag
	gameplay/res/shaders/textured.frag
	samples/browser/res/common/box.material
	samples/browser/res/common/duck.material
	samples/browser/res/common/sample.material
	samples/browser/src/PostProcessSample.cpp
	samples/character/src/CharacterGame.cpp
	samples/lua/res/box.material
	samples/lua/res/game.lua
	samples/mesh/res/duck.material
	samples/mesh/src/MeshGame.cpp
	samples/spaceship/src/SpaceshipGame.cpp