Merge pull request #1 from fz1989/master

完成第四章
加入第四章到目录，并把fz1989加入到贡献名单
Update README.md

fix display error in readme
Update README.md
第二章完成
Update README.md
Update README.md
Update README.md
Update README.md
Update README.md
Update README.md
Update README.md
Update README.md
Update 04.0.md
Update 04.0.md
add the Chapter 9
update the Chapter 9
Delete .DS_Store

delete DS_Store
Update README.md
Update README.md