fix UIWidget._positionPercent issue;
UILoadingBar: replaced addChild() with addProtectedChild() to add _barRenderer;
Merge pull request #2282 from mutoo/fix_bugs

Fix some bugs in ccui;
Feature #5941: Activate WebGL for iOS
TODO: need to specify version
Merge branch 'develop' of git://github.com/cocos2d/cocos2d-html5 into develop
Fixed #5948: Fix touch event bug with multitouch on iOS
Remove Timeline.js
Merge pull request #2287 from VisualSJ/timeline2

Remove TimeLine.js
Create Timeline.js
Merge pull request #2288 from VisualSJ/timeline2

Create Timeline.js
Fixed #5949: Add type check in cc.loader
Fixed #5949: Add type check in cc.loader
Merge branch 'develop' of git://github.com/cocos2d/cocos2d-html5 into develop
Merge pull request #2289 from pandamicro/develop

Activate WebGL for iOS
Issue #5941: refactor UILayout for new renderer
Merge branch 'Renderer' of https://github.com/cocos2d/cocos2d-html5 into Iss5941_WebGLRenderer
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-html5 into Iss5941_WebGLRenderer
Merge pull request #2294 from dingpinglv/Iss5941_WebGLRenderer

Issue #5941: refactor UILayout for new renderer