closed #3128: Fix a bug of Sprite that it is not to be set transform dirty when set color and opacity.
Merge pull request #1217 from xingsenma/bug_3128_sprite

closed #3128: Fix a bug of Sprite that it is not to be set transform dirty when set color and opacity.
fixed #3120: replacing cc.Assert for better performance.
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-html5 into Iss3120_ReplaceCCAssert