Change positions of codes.
Change getInfo to dumpInfo.
Add `loadAliases` to `cc.loader`.
Fix a bug of `loadAliases`.
Merge branch 'develop-3.0' of https://github.com/cocos2d/cocos2d-html5 into CCGame_dev3.0

Conflicts:
	CCBoot.js
Move `cc.sys` into `CCBoot.js`.
Refactor something about `cc._renderType`.
Remove `cc.sys.supportWebGL`.
Change some public apis to private.
Merge pull request #1634 from SmallAiTT/CCGame_dev3.0

issue #3935 Refactor `cc.sys`.