Allow to configure pool name for notifications

enable it by default with pool name 'barbican'.

Change-Id: Id109c34b4ac0ae0250a28b570768ea64b074a173
Related-Issue: PROD-31028
diff --git a/README.rst b/README.rst
index 47f3e6d..c7cf95c 100644
--- a/README.rst
+++ b/README.rst
@@ -145,19 +145,28 @@
 
 To enable keystone notification listener, set the `ks_notification_enable`
 to true.
+
 `ks_notifications_allow_requeue` enables requeue feature in case of
 notification processing error. Enable this only when underlying transport
 supports this feature.
 
+`ks_notifications_pool_name` allows to use keystone listener together with
+other applications listening on the same notifications topic without
+interference between services. Set it to any distinctive value to enable
+listener pooling. It is enabled by default with pool name 'barbican'.
+Disable it (by setting to empty string) only if underlying messaging transport
+does supports this feature or Barbican is the sole service listening for
+notifications on 'notifications' topic.
 
 .. code-block:: yaml
 
     barbican:
       server:
         enabled: true
-        version: ocata
+        version: pike
         ks_notifications_enable: true
         ks_notifications_allow_requeue: true
+        ks_notifications_pool_name: barbican
 
 
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