auto fix
Merge branch 'bowen' into rtong
fix ws
Merge branch 'bowen' into rtong

Conflicts:
	app/views/stu_course.scala.html
	public/javascripts/action.js
ff
Merge branch 'rtong' into shuaiwang

Conflicts:
	app/controllers/StudyPlanController.java
	app/controllers/algorithm/pre_and_core/CrossLinkedList.java
lalala
add assign
Merge branch 'shuaiwang' into Bohan-Zheng