issue #4221 add some getter method .
issue #4221 add read "selectedState"
issue #4174 fix scale bug for button.
issue #4174 fix layoutParameter clone bug.
issue #4221 refactor addNode and addChild for widget
issue #4221 fixed frame event emit twice times
issue #4221 add removeByComponent for ComponentContainer
issue #4221 delete UILayout and CompatibleClasses
Merge branch 'develop-3.0' of https://github.com/cocos2d/cocos2d-html5 into develop-3.0-new
Merge pull request #1620 from xingsenma/develop-3.0

issue #4221 update cocostudio gui to 3.0