Merge pull request #86 from NicoleRauch/master

Datenbank sortiert Listen jetzt sinnvoll
Now we can retrieve a list of objects from a list of IDs.
err should be passed to done() whenever it is available.
Cleanup of getGroup()
Test cleanup.
Cleanup around createGroup and saveGroup.
Cleanup around createOrSaveGroup.
First attempt of displaying the members of a group.
emergency bugfix

Earlier commit killed new user forward
Adapted tests to new member query function. (Tests need to be reworked...)
Merge remote-tracking branch 'upstream/master'