Update docs

See merge request thalia/concrexit!642

Change the volumes docker-compose.yml

See merge request thalia/concrexit!646

Fix careers page ui on mobile

Closes #440

See merge request !631

Speed up CI

See merge request !641

Docs Sphinx Dockerfile

See merge request !635

Improve registrations tests

See merge request !645

Hard-code dates set with freezegun to make the tests easier to read
and more explicit.

This new dockerfile includes ghostscript, pip and apt so it should speed up the build significantly

Fix registrations services tests

Closes #553

See merge request !644

Explain/Warn about committeememberships in admin

See merge request !630

Fix missing context in /me members API call

See merge request !639

Fix missing avatar key in member serializer

See merge request !638

Added a check for starting_year and programme_display

Closes #510

See merge request !632

Fix photo uri in events API

See merge request !637

Use DRF's get_object_or_404 instead of the default in the pizzas viewset

See merge request !628

added a category field and added it to the admin with filtering

Closes #537

See merge request !634

Add backwards compatible avatar object to events and members API for better thumbnails

Closes #527

See merge request !636

Merge branch '516-als-admin-is-de-tijd-die-in-het-evenementenoverzicht-staat-hetzelfde-als-de-tijd-die-staat-ingesteld-bij-het-evenement' into 'master'

Made the start date a naive when being sent to the admin overview page.

Closes #516

See merge request !626

Use get for dict access in order serializer

See merge request !629

Add start and end query parameters to events API

Closes #547

See merge request !623

Fix documents page font

See merge request !624