Add basic views for managing seating plans

aleksis/apps/stoelindeling/forms.py

aleksis/apps/stoelindeling/menus.py

aleksis/apps/stoelindeling/migrations/0001_initial.py

aleksis/apps/stoelindeling/rules.py

aleksis/apps/stoelindeling/tables.py

...sis/apps/stoelindeling/templates/stoelindeling/empty.html

...indeling/templates/stoelindeling/seating_plan/create.html

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

...elindeling/templates/stoelindeling/seating_plan/list.html

...elindeling/templates/stoelindeling/seating_plan/view.html

aleksis/apps/stoelindeling/urls.py

aleksis/apps/stoelindeling/views.py