Issue #4757: update a mistake of CHANGELOG
Merge branch 'master' of https://github.com/cocos2d/cocos2d-js into Iss4757_ReleaseV3_A2
Issue #4757: update the reference of cocos2d-html5
Merge pull request #272 from dingpinglv/Iss4757_ReleaseV3_A2

Issue #4757: correct a mistake of CHANGELOG and the reference of cocos2d-html5