Fix keyerror on registration

See merge request !63

Raise version

See merge request !62

Translations update from Weblate

See merge request !61

Currently translated at 96.4% (27 of 28 strings)

Translation: Hack'n'Fun/AlekSIS-App-Paweljong-Frontend
Translate-URL: https://translate.edugit.org/projects/hacknfun/aleksis-app-paweljong-frontend/de/

Translations update from Weblate

See merge request !59

Fix event additional field title

See merge request !60

Currently translated at 96.4% (27 of 28 strings)

Translation: Hack'n'Fun/AlekSIS-App-Paweljong-Frontend
Translate-URL: https://translate.edugit.org/projects/hacknfun/aleksis-app-paweljong-frontend/de/

Update formtools and dependencies

See merge request !58

Resolve "Remove person from group if registration is retraced"

Closes #50

See merge request !53

Resolve "Remove additional fields support and re-implement additional fields in paweljong"

Closes #58

See merge request !54

Merge remote-tracking branch 'origin/58-remove-additional-fields-support' into 58-remove-additional-fields-support

# Conflicts:
#	aleksis/apps/paweljong/frontend/components/event_additional_field/EventAdditionalFieldList.vue
#	aleksis/apps/paweljong/frontend/messages/en.json
#	aleksis/apps/paweljong/schema.py