Merge pull request #51 from chaffeqa/patch-1

Fix missing operation_name warning

Author: syrusakbary

graphene_django/templates/graphene/graphiql.html

@@ -112,7 +112,7 @@
         {% if variables %}
         variables: '{{ variables|escapejs }}',
         {% endif %}
-        {% if operationName %}
+        {% if operation_name %}
         operationName: '{{ operation_name|escapejs }}',
         {% endif %}
       }),