Add Join Event method
Add Confirm/Decline functionality
Merge branch 'master' of https://github.com/amandziy/StartItUp

Conflicts:
	src/main/java/com/eventposter/controller/EventUserController.java
	src/main/java/com/eventposter/facade/EventFacade.java
	src/main/java/com/eventposter/facade/EventUserFacade.java