Allow admin and course teacher to edit course.
Merge branch 'master' of https://github.com/jasli2/evolution
Add user relationship which can follow/unfollow user.
Update field for course. Add lesson to store video for course. NOT DONE YET.
Update header menu and left menu. Add flash player support for course.
Merge ll's pull request : Add zh_CN for admin .
add course export zh-CN
view header add zh-CN
Add zh-CN for Users
Add zh-CN for courses
Add zh-CN for user new
Add zh_CN for competency