* check for payment method instead of order total
* incorporate payment fee diff in totaldiff at oder change
* use fee from model and the correct order total
* add error handling
* do not change paid orders
* OrderChangedManager can only be committed once
* remove prints of stripe secrets
* add tests
* an OrderChangeManager must not be committed multiple times
* A pending free order stays pending after being changed
* comments on paid_to_free logic
* New concept for fee handling
* More usages
* Remove all usages, make all tests pass
* API changes
* Small fixes
* Fix order of invoice lines
* Rebase migration
* 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
