user crud and groups crud implemented
Merge remote-tracking branch 'origin/master'

Conflicts:
	web/pom.xml
	web/src/main/java/dbd/web/controller/AssignmentController.java
	web/src/main/webapp/WEB-INF/jsp/activities.jsp
	web/src/main/webapp/WEB-INF/jsp/home.jsp
	web/src/main/webapp/index.jsp