add chapert 4
fixed #3343. Finish chapter5 of Parkour game with cocos2d-html5
fixed #3343. modify some misspell words
fixed #3343. modify paragraph of TexturePacker
add download link
fixed #3343. Finish the tutorial
Merge pull request #14 from andyque/chapter5

Chapter5 of Parkour with cocos2d-html5 game