* mention CoC in README.md
According to the discussion in #689, the Code of Conduct gets directly
referenced in the README-file, instead of linking to the
CODE_OF_CONDUCT-file
* undo whitespace-change
* Data model and migration
* Some backwards compatibility
* CRUD for checkin lists
* Show and perform checkins
* Correct numbers in table and dashboard widget
* event creation and cloning
* Allow to link specific exports and pass options per query
* Play with the CSV export
* PDF export
* Collapse exports by default
* Improve PDF exporter
* Addon stuff
* Subevent stuff, pretixdroid tests
* pretixdroid tests
* Add CRUD API
* Test compatibility
* Fix test
* DB-independent sorting behavior
* Add CRUD and coyp tests
* Re-enable pretixdroid plugin
* pretixdroid config
* Tests & fixes
* MKBDIGI-183: Added quotas API write methods
* MKBDIGI-183: Fixed code formatting
* MKBDIGI-183: Added test for permission requirements
* MKBDIGI-183: Documentation corrections
* MKBDIGI-183: Removed redundant create/update locks
* MKBDIGI-183: Added quota validation to check that items and variations corresponds to each other
* MKBDIGI-183: Added quota validation to check that item belong to the same event as the endpoint
* MKBDIGI-183: Added subevent validation to check that subevent belong to the same event as the endpoint
* MKBDIGI-183: Added subevent validation to check that subevent is null for non-series events
* MKBDIGI-183: Changed validation error text
* MKBDIGI-183: Added logging for subevents
* MKBDIGI-183: Fixed code formatting
* MKBDIGI-183: Fixed validation error in API test
* MKBDIGI-183: Fixed documentation errors
* MKBDIGI-183: Fixed typos in validation messages
* MKBDIGI-183: Refactored validation loop vars check
* MKBDIGI-183: Updated error strings in test assersions
* MKBDIGI-183: Fixed logging for API quota update to account changing subevents
