Show moderation and inactive stores to admins

* Add better admin interface for FlaggedObject
* Export totals via context processors
* Update base template to show this data to admins.

app/moderation/context_processors.py

@@ -0,0 +1,10 @@
+from django.contrib.sites.models import Site
+from moderation.models import FlaggedObject
+
+def pending_flagged_admin(request):
+    if request.user.is_superuser:
+        pending_flags = FlaggedObject.objects.filter(status=1).count()
+        return {
+            'admin_pending_flags': pending_flags
+        }
+    return {}