Added a way to see that ES is in use for API search.

apps/api/templates/api/search.xml

@@ -1,4 +1,5 @@
 <?xml version="1.0" encoding="utf-8" ?>
+{% if using_ES %}<!-- Using elasticsearch. Hi Krupa! -->{% endif %}
 <searchresults total_results="{{ total }}">
   {% if addons_xml %}
       {% for xml in addons_xml %}

apps/api/views.py

@@ -339,6 +339,7 @@ class SearchView(APIView):
         qs = qs.filter(**filters)
 
         return self.render('api/search.xml', {
+            'using_ES': True,
             'results': qs[:limit],
             'total': qs.count(),
         })