Add a document to describe how to call c++ from lua
change cocos2d-js download url
Merge Cocos2d-JS v3.0 alpha2 and V2.2.3 to the summary of release note.
Add more information part.
updated download link
Merge pull request #258 from linshun/master

Merged Cocos2d-JS v3.0 alpha2 and Cocos2d-html5 v2.2.3 to the summary of release note.
Merge pull request #257 from pandamicro/master

[Cocos2d-JS] Improve release notes and catalog
Merge pull request #256 from samuele3hu/luaDocument

Add a document to describe how to call c++ from lua
correct debug lua url
Merge pull request #259 from honghui/master

correct urls
[Cocos2d-JS] Add js about docs