dashboard: fix multiple warning messages

circle/dashboard/views.py

@@ -543,6 +543,13 @@ class TemplateAclUpdateView(AclUpdateView):
             logger.warning('Tried to set permissions of %s by non-owner %s.',
                            unicode(template), unicode(request.user))
             raise PermissionDenied()
+
+        name = request.POST['perm-new-name']
+        if (User.objects.filter(username=name).count() +
+                Group.objects.filter(name=name).count() < 1
+                and len(name) > 0):
+            warning(request, _('User or group "%s" not found.') % name)
+        else:
             self.set_levels(request, template)
             self.add_levels(request, template)