Closed #3427: add some public function to event manager and hide some event listener to private
Merge branch 'develop-3.0' of https://github.com/cocos2d/cocos2d-html5 into Iss3427_NewEventDispatcher

Conflicts:
	cocos2d/core/event-manager/CCEventManager.js
Merge pull request #1621 from dingpinglv/Iss3427_NewEventDispatcher

Closed #3427: add some public function to event manager and hide some event listener to private