Merge pull request #17 from cloudaice/master

在把body体转成json格式的时候没有错误处理
polish docstrings
Merge pull request #18 from antiAgainst/master

polish docstrings
revise README
Merge pull request #19 from antiAgainst/master

revise README
create new README for pip and update version to 1.1.0
raise AttributeError than KeyError to make pickle works
fix urlencode of list params
add refresh_token
Merge pull request #1 from michaelliao/master

sync code