Move AKModel views into several subfiles to improve overview and resolve problems with circular imports
Introduce new modular status page handling (widgets and views)
Port main status page to new structure
Move AK messages status page visualization to AKSubmission (therefore, they automatically do not show up when there is no possibility to create them)
Introduce status widget for virtual rooms
Fix timezone issue for rendering of AK messages on status page
Adapt status page URL in several views and tests

Use One2One relationship instead of inheritance
This allows to add and also remove the virtual features of a room

Introduce new model
Create migrations to migrate from existing to new model + a squashed version knowing only about the new model for fresh installations
Adapt admin views
Add django-betterforms as dependency to simply create a form allowing to generate rooms with optionally a virtual component in a single view and create that form
Add view to create rooms in that view and use instead of default django creation form
Use the new name/structure in templates
Move RoomForm to forms.py to make imports easier
Update batch creation of rooms

This resolves #150 and also resolves #179 since now rooms and virtual rooms (rooms with virtual features) are created using the same view