Closed #3120: cc.Assert has been replaced, it is very slow.
fixed #3120: replacing cc.Assert for better performance.
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-html5 into Iss3120_ReplaceCCAssert
Merge pull request #1218 from dingpinglv/Iss3120_ReplaceCCAssert

Closed #3120: cc.Assert has been replaced, it is very slow.