Merge pull request #320 from yinjimmy/develop

update welcome app
move docs to https://github.com/chukong/cocos-docs
Merge branch 'develop' of github.com:chukong/quick-cocos2d-x into develop
fix touch problems
add CCNode:resetCascadeBoundingBox()
Merge branch 'develop' of https://github.com/yinjimmy/quick-cocos2d-x into develop