add kaminari
merge master
add user email validate spec
add file upload controller spec
rm public/test
update gitignore
完成分段上传js基本逻辑
update upload javascript
add MediaResource#size
add some methods to MediaResource
完成资源文件删除逻辑
update css
完成网盘基础逻辑
merge master, 增加网盘功能
refactor media_resource
refector uploader
Update README.md

增加coveralls的代码覆盖率统计
refector course import
重构用户导入
Merge branch 'master' of github.com:mindpin/eshare