edits from corina in LoginManager, User and Authentification Process
Merge branch 'master' of
https://github.com/sirlordrouter/ch.bfh.btx8081.w2013.green.git

Conflicts:
	src/main/java/ch/bfh/btx8081/w2013/green/businesslogic/LoginManager.java
	src/main/java/ch/bfh/btx8081/w2013/green/data/RegisteredUserDB.java
	src/main/java/ch/bfh/btx8081/w2013/green/data/User.java
	src/main/java/ch/bfh/btx8081/w2013/green/ui/start/MyVaadinUI.java
	src/main/java/ch/bfh/btx8081/w2013/green/ui/state/AuthenticatedState.java