added DAO and added "addSUbject" feature at admin side.
added DAO and added "addSUbject" feature at admin side.
Merge origin/master

Conflicts:
	src/main/java/cs544/letmegiveexam/controller/LoginController.java
	src/main/java/cs544/letmegiveexam/service/SubjectService.java
	src/main/webapp/WEB-INF/springmvc-servlet.xml
	src/main/webapp/WEB-INF/views/welcome.jsp