Add field to model
Use field in form
Display field in ak detail view

Show track in ak detail view
Update translations

Closes #60
Add boolean flag to event
Hide plan for non-staff users when flag is set
Update translations

Closes #77
Show link button for virtual rooms
Display capacity and properties
Link in detail view (plan and table)
Update translations

availabilities in AK submission
availabilities in AK wish submission

Introduce new mixin
Replace edit & create views by redirects to overview page
Prevent inserting/updating for AKs and Owners
Disable interest counter
Hide interest button
Update translations

Hide wall (hide button in plan, redirect when calling directly)
Show message on normal plan & hide current and next AKs
Link only a single schedule view in Dashboard but not current AKs and wall
Update translations

adjust other buttons
re-generate translations

Adapt filenames, references and URLs
Adapt settings keys
Adapt translations
Fix wrong settings keys in wall view

Add views
Add templates
Add urls
Add translations
Add three corresponding settings to central settings file
Minor: Fix typo in plan_akslot