FK bug fixed
modify database, but there is login bug
Merge branch 'master' of https://github.com/SweenEy1130/GeenZen

Conflicts:
	ChunTsung/app/models/Application.java
	config/init_struct.sql
	config/init_user.sql
correct the bug but the metor_uid still not found
Merge branch 'master' of https://github.com/SweenEy1130/GeenZen

Conflicts:
	ChunTsung/app/controllers/FormManage.java
	ChunTsung/app/models/Application.java
	ChunTsung/app/models/Student.java
	ChunTsung/app/models/Topic.java
	ChunTsung/app/views/formView/mentor_proposal.scala.html
	config/init_struct.sql
	config/init_user.sql