CCProtocols: Making opacity and color properties in the CCRGBAProtocol.
1) Implemented cascading color to CCNodeRGBA and CCLayerRGBA (works in the same way as cascading opacity). Use the CC_CASCADING_COLOR option in ccConfig.h.
2) It is now possible to disable cascading opacity and cascading color at node level. Use cascadeOpacity and cascadeColor properties.