review

labelttf and layers have reviewed.
Merge branch 'develop' of https://github.com/pascallin/cocos2d-html5 into develop

Conflicts:
	cocos2d/core/labelttf/CCLabelTTF.js
	cocos2d/core/labelttf/LabelTTFPropertyDefine.js
	cocos2d/core/labelttf/LabelTTFWebGL.js
	cocos2d/core/layers/CCLayer.js
	cocos2d/core/layers/CCLayerPropertyDefine.js
	cocos2d/core/layers/CCLayerWebGL.js