Allow to manually exclude quotas from calendar availability

src/pretix/control/templates/pretixcontrol/items/quota_edit.html

@@ -41,6 +41,7 @@
             <legend>{% trans "Advanced options" %}</legend>
             {% bootstrap_field form.close_when_sold_out layout="control" %}
             {% bootstrap_field form.release_after_exit layout="control" %}
+            {% bootstrap_field form.ignore_for_event_availability layout="control" %}
         </fieldset>
         <div class="form-group submit-group">
             <button type="submit" class="btn btn-primary btn-save">

src/pretix/control/templates/pretixcontrol/items/quotas.html

@@ -66,6 +66,9 @@
                     <tr>
                         <td>
                             <strong><a href="{% url "control:event.items.quotas.show" organizer=request.event.organizer.slug event=request.event.slug quota=q.id %}">{{ q.name }}</a></strong>
+                            {% if q.ignore_for_event_availability %}
+                                <span class="fa fa-eye-slash text-muted" data-toggle="tooltip" title="{% trans "Ignore this quota when determining event availability" %}"></span>
+                            {% endif %}
                         </td>
                         <td>
                             <ul>