change the init method  int class config.cs  in case the  config  be null
Merge pull request #59 from zheniantoushipashi/change-config-class

change the init method  int class config.cs  in case the  config  be nul...
add mkzip class
Merge pull request #62 from zheniantoushipashi/add-mkzip

add mkzip class
Merge pull request #64 from HADB/develop

添加了fetch操作
Merge pull request #1 from qiniu/develop

merge from qiniu