Fixing a bug regarding an interaction of cascading opacity and cascading color affecting the unmodifiedColor variable within CCSprites.
Merge remote-tracking branch 'rsanchezsaez/rsanchezsaez-v2-cascading-opacity' into develop-v2

Conflicts:
	cocos2d/CCLabelBMFont.m
	cocos2d/CCLayer.m
	cocos2d/CCNode.m