splash screen for not logged in users is factory preset atrium

This is in purpose. User account creation was possible in the previous version, but was not working, as there was a huge amount of spammers and too little time from the admins to manually go through the queue and approve valid e-mails.

The idea is to make the site invite-only, i.e. registered users can send links to others to join. But this requires some development.

But the landing page will still needs work, would be nice to come out with a concept or at least adapt it a bit, so I am keeping this issue open, changing to feature request.