Fixed #5742: Support remote image in cc._imgLoader and cc.textureCache.addImage
Fixed #5742: Improve cc.textureCache.addImage
Issue #5781: Clean up game start up code
Update plugin-x ref for FacebookAgent
Fixed #5760: Improve templates HelloWorld project
Merge branch 'master' of https://github.com/cocos2d/cocos2d-js
Merge pull request #644 from pandamicro/master

Fixed #5742: Support remote image in cc._imgLoader and cc.textureCache.addImage