Add a cancel button on the add form.

django/website/hid/templates/hid/add_edit_item.html

@@ -97,6 +97,7 @@
                     {% else %}
                         <div class="form-group btn-group pull-right">
                             {% bootstrap_button "Create" button_type="submit" name="action" value="create" button_class="pull-right btn btn-sm btn-success" %}
+                            {% bootstrap_button "Cancel" button_type="submit" name="action" value="cancel" button_class="pull-left btn btn-sm" %}
                         </div>
                     {% endif %}
                 </div>