Implement view for editing a seating plan

aleksis/apps/stoelindeling/forms.py

aleksis/apps/stoelindeling/managers.py

...is/apps/stoelindeling/migrations/0002_seat_auto_create.py

aleksis/apps/stoelindeling/models.py

aleksis/apps/stoelindeling/settings.py

...s/stoelindeling/static/css/stoelindeling/seating_plan.css

...toelindeling/static/js/stoelindeling/edit_seating_plan.js

.../stoelindeling/templates/stoelindeling/partials/seat.html

...elindeling/templates/stoelindeling/seating_plan/edit.html

aleksis/apps/stoelindeling/views.py