Add required param `renderer` to Widget.render

Added on Django 1.11 and required since 2.1
The renderer argument is added to the Widget.render() method.
https://docs.djangoproject.com/en/2.1/releases/1.11/#id2

orchestra/forms/widgets.py

@@ -17,9 +17,9 @@ class SpanWidget(forms.Widget):
         self.original = kwargs.pop('original', '')
         self.display = kwargs.pop('display', None)
         super(SpanWidget, self).__init__(*args, **kwargs)
-    
-    def render(self, name, value, attrs=None):
-        final_attrs = self.build_attrs(attrs, name=name)
+
+    def render(self, name, value, attrs=None, renderer=None):
+        final_attrs = self.build_attrs(attrs, extra_attrs={'name':name})
         original = self.original or value
         display = original if self.display is None else self.display
         # Display icon
@@ -29,10 +29,10 @@ class SpanWidget(forms.Widget):
         tag = self.tag[:-1]
         endtag = '/'.join((self.tag[0], self.tag[1:]))
         return mark_safe('%s%s >%s%s' % (tag, forms.utils.flatatt(final_attrs), display, endtag))
-    
+
     def value_from_datadict(self, data, files, name):
         return self.original
-    
+
     def _has_changed(self, initial, data):
         return False
 
@@ -61,7 +61,7 @@ class DynamicHelpTextSelect(forms.Select):
         attrs.update(kwargs.get('attrs', {}))
         kwargs['attrs'] = attrs
         super(DynamicHelpTextSelect, self).__init__(*args, **kwargs)
-    
+
     def get_dynamic_help_text(self, target, help_text):
         return textwrap.dedent("""\
             siteoptions = {help_text};