delete
fix
Merge branch 'bowen' into shuaiwang
Merge branch 'Bohan-Zheng' into shuaiwang
Merge branch 'master' into shuaiwang
Merge branch 'bowen' into shuaiwang
add find corerequsite
Merge branch 'Bohan-Zheng' into shuaiwang
Merge branch 'Bohan-Zheng' into shuaiwang
version1.5
Merge branch 'rtong' into Bohan-Zheng
Merge branch 'rtong' into Bohan-Zheng
version2.0
add core requisite
Merge branch 'shuaiwang' into Bohan-Zheng

Conflicts:
	app/models/StudyPlan.java
update new algorithm
fix unassign course
version2.1
Merge branch 'Bohan-Zheng' into shuaiwang
Merge branch 'shuaiwang' into Bohan-Zheng