Merge pull request #20 from coursemology-collab/wangqiang/course-models

course and enrolment models
install gem cancancan
ability class to handle permissions of admin
Merge pull request #24 from coursemology-collab/wangqiang/authorization

authorization using cancancan
Use travis' container infrastructure
Merge pull request #27 from jsyeo/jsyeo-travis-container

Use travis' container infrastructure
install gem simple_form
rails generate courses controller
default empty actions and routes
new and create action
edit and update action