Add back extra docs

Author: jkimbo

docs/filtering.rst

@@ -107,6 +107,34 @@ features of ``django-filter``. This is done by transparently creating a
 ``django_filters.FilterSet`` class for you and passing in the values for
 ``filter_fields``.
 
+However, you may find this to be insufficient. In these cases you can	
+create your own ``FilterSet``. You can pass it directly as follows:	
+
+.. code:: python	
+
+    class AnimalNode(DjangoObjectType):
+        class Meta:
+            # Assume you have an Animal model defined with the following fields
+            model = Animal
+            filter_fields = ['name', 'genus', 'is_domesticated']
+            interfaces = (relay.Node, )
+
+
+    class AnimalFilter(django_filters.FilterSet):
+        # Do case-insensitive lookups on 'name'
+        name = django_filters.CharFilter(lookup_expr=['iexact'])
+        class Meta:
+            model = Animal
+            fields = ['name', 'genus', 'is_domesticated']
+
+
+    class Query(ObjectType):
+        animal = relay.Node.Field(AnimalNode)
+        # We specify our custom AnimalFilter using the filterset_class param
+        all_animals = DjangoFilterConnectionField(AnimalNode,
+                                                  filterset_class=AnimalFilter)
+
+
 You can also specify the ``FilterSet`` class using the ``filterset_class``
 parameter when defining your ``DjangoObjectType``, however, this can't be used
 in unison  with the ``filter_fields`` parameter:
@@ -129,8 +157,8 @@ in unison  with the ``filter_fields`` parameter:
         class Meta:
             model = Animal
             fields = ['name', 'genus', 'is_domesticated']
-            
-            
+
+
     class AnimalNode(DjangoObjectType):
         class Meta:
             # Assume you have an Animal model defined with the following fields