Conflicts:
	src/main/java/de/thm/arsnova/socket/ARSnovaSocketIOServer.java

Properties from properties file are available in all beans now.
CouchDB connection in SessionService will be created using these settings.
If a connection fails, the next request will have a new try instead of
throwing an exception.

leiten

* Make guest login working with new UserService
* Reuse existing guest username
* Adapted tests

This method uses transaction level READ_COMMITTED.

switch to oauth2 authentication which allows facebook, twitter, google
etc authentication

add spring-test and junit
add jetty plugin which allows mvn jetty:run

redirection

include config.properties.example and let override values by
config.properties
cas spring security configuration adjustments 

A session will be returned if one of the following cases are true:
* the session is active
* the session is inactive AND current (logged in) user is the creator