Closed #5845: Fixed a bug of InputManager, its first touch move event's delta is wrong.
Merge branch 'develop' of git://github.com/cocos2d/cocos2d-html5 into Iss5845_InputManager
Merge pull request #2162 from dingpinglv/Iss5845_InputManager

Closed #5845: Fixed a bug of InputManager, its first touch move event's delta is wrong.