* [WIP] manual check-in of attendees
This enables manual check-in of attendees. The post-code was heavily
copied from the APIRedeemView of the pretixdroid, thus so far this seems
to be working, but I have a few questions:
The checkin-Objects generated by the pretixdroid-app have a nonce.
Should the checkin object generated here have a nonce, too?
Should the result of the check-in be noted in any other way than by the
change of the status?
* addressed review comments
* implement unit test for manual checkin
* fix style-issues
* Slight layout change
* Log who did the manual check-in
* Improve unit test to check the result of the action
* Data model
* little crud
* SubEventItemForm etc
* Drop SubEventItem.active, quota editor
* Fix failing tests
* First frontend stuff
* Addons form stuff
* Quota calculation
* net price display on EventIndex
* Add tests, solve some bugs
* Correct quota selection in more places, consolidate pricing logic
* Fix failing quota tests
* Fix TypeError
* Add tests for checkout
* Fixed a bug in QuotaForm
* Prevent immutable cart if a quota was removed from an item
* Add tests for pricing
* Handle waiting list
* Filter in check-in list
* Fixed import lost in rebase
* Fix waiting list widget
* Voucher management
* Voucher redemption
* Fix broken tests
* Add subevents to OrderChangeManager
* Create a subevent during event creation
* Fix bulk voucher creation
* Introduce subevent.active
* Copy from for subevents
* Show active in list
* ICal download for subevents
* Check start and end of presale
* Failing tests / show cart logic
* Test
* Rebase migrations
* REST API integration of sub-events
* Integrate quota calculation into the traditional quota form
* Make subevent argument to add_position optional
* Log-display foo
* pretixdroid and subevents
* Filter by subevent
* Add more tests
* Some mor tests
* Rebase fixes
* More tests
* Relative dates
* Restrict selection in relative datetime widgets
* Filter subevent list
* Re-label has_subevents
* Rebase fixes, subevents in calendar view
* Performance and caching issues
* Refactor calendar templates
* Permission tests
* Calendar fixes and month selection
* subevent selection
* Rename subevents to dates
* Add tests for calendar views
* New models
* CRUD UI
* UI for adding/removing team members
* Log display for teams
* Fix invitations, move frontend
* Drop old models (incomplete)
* Drop more old stuff
* Drop even more old stuff
* Fix tests
* Fix permission test
* flake8 fix
* Add tests fore the new code
* Rebase migrations
