add hello word index.html.
Merge branch 'master' of https://github.com/cocos2d/cocos-docs into gh-pages
modify folder name, replace ‘_’ to ‘-’  .
delete index.html. modify catalog tutorials’ list.
Merge pull request #93 from Ivenyang/master

modify folder name - replace '_' to '-'.
Edited for spelling, grammar, and clarity.
Merge pull request #94 from bunnyhero/event-dispatcher-mechanism

Edited for spelling, grammar, and clarity.
Added catalog/ja.md
Merge pull request #95 from tks2shimizu/Catalog_ja

Added catalog/ja.md
Merge remote-tracking branch 'upstream/master'