Added error message when redirecting to activities/edit
Merge commit '8c77c61e6c34f6a9a67cca215176f48d18238c01'
Merge commit '7b1190eea4cf2f885f380224c3721a9a5273635b'
Now our test-app is equipped with a session -> tests now work even when a statusmessage is created (and added to the session...) in production code.
Merge commit '6b539bd9c9f289956a2f0a03bc59919813aba643'
Merge pull request #591 from NicoleRauch/master

Fehlermeldung beim Speicherkonflikt während der Bearbeitung einer Activity