* Upgrade Django to 3.0 and other dependencies to recent versions
* Fix otp version contsraint
* Remove six dependency
* Resolve some warnings
* Fix failing tests
* Update django-countries
* Resolve all RemovedInDjango31Warnings in test suite
* Run isort
* Fix import
* Update PostgreSQL version on travis
* Drop support for maindomain_urls/subdomain_urls in plugins
* Allow to use a custom domain per event
* Fix bug when manually saving domains
* Fix custom domains in debugging
* Fix middleware
* Fix middleware again, update docs
* Add testmode-support-flag to SalesChannels
* Make saleschannels/testmode-warnings even more dangerous!
* Add warning for payment-methods that do support testmode but are being used in a non-testmode order caused by a saleschannel in a testmode-shop.
* Remove redundant testmode_supported-flag for WebshopSalesChannel
* Raise error on API when sales_channel does not support testmode
* Tests
* Fix style issue after merge
- [x] Data model
- [x] Enforce constraint
- [x] Filter order list
- [x] Set channel on created order
- [x] Products API
- [x] Order API
- [x] Tests
- [x] Filter reports
- [x] Resellers
- [ ] deploy plugins
- [ ] posbackend
- [ ] resellers
- [ ] reports
- [x] Ticketlayouts
- [x] Support in pretixPOS
* 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
This simplifies providing an `event_view` method which works as
decorator for presale/ views (e.g. for plugins), providing passing
requests with event and organizer context if possible, and re-routing or
failing appropriately otherwise.