Refactored CCEffectNode and CCEffects so that they can support multiple render passes.
Added a glow/bloom effect.

TODO: add multi pass guassian blur to CCEffectGlow instead of doing it in place (way to slow)
TODO: add a way for sprites to extract a cceffectnode texture and update them selfs without the need to rendering everything to a cceffectnode
TODO: refactor CCEffectRenderPass (see comments left in code)
TODO: make sure CCEffectNode render correctly when auto drawing
TODO: add a dirty flag/use the renderer caching logic to avoid extra calls to cceffect node.
TODO: make sure all other basic effects still work as expected with the new refactor of CCEffectNode