Update documentation related to hazelcast

- removed old entries of data structures which are removed now.
- updated the documentation to correctly reflect our infrastructure
  startegy related to hazelcast.
- fixed few NB comments on the merged patch.

Issue-ID: CPS-2408
Change-Id: Id7ce4ac695ad94742490ac5d2be89cd23ffda3e5
Signed-off-by: mpriyank <priyank.maheshwari@est.tech>
diff --git a/docs/release-notes.rst b/docs/release-notes.rst
index cebb1c0..9c08356 100644
--- a/docs/release-notes.rst
+++ b/docs/release-notes.rst
@@ -43,6 +43,7 @@
 Features
 --------
 3.5.4
+    - `CPS-2408 <https://lf-onap.atlassian.net/browse/CPS-2408>`_ One Hazelcast instance per JVM to manage the distributed data structures.
 
 Version: 3.5.3
 ==============