Release Notes upgraded

We have added Release notes to the landing page,
corrected release note label for Dublin, updated
release info in Overview doc, removed overlapping
content from Release Notes (content available
in Overview)

Change-Id: Ib03c38abfa115fd10cb0f8c64877ee140d6fece3
Issue-ID: DOC-471
Signed-off-by: Noemi Wagner <noemi.wagner@nokia.com>
diff --git a/docs/guides/overview/overview.rst b/docs/guides/overview/overview.rst
index 83c7e9d..fc45705 100644
--- a/docs/guides/overview/overview.rst
+++ b/docs/guides/overview/overview.rst
@@ -152,7 +152,9 @@
 +----------------------+----------------+----------------------+-----------------------------------------------------------+
 |Release Name          |Release version |Release Date          |Features delivered                                         |
 +======================+================+======================+===========================================================+
-|Casablanca            |* 3.0.2         |* 31 January 2019     | :ref:`Casablanca Release Notes <casablancarelease-notes>` |
+|Dublin                |4.0.0           |2019                  | :ref:`Dublin Release Notes <dublinrelease-notes>`         |
++----------------------+----------------+----------------------+-----------------------------------------------------------+
+|Casablanca            |* 3.0.2         |* 31 January 2019     |                                                           |
 |                      |* 3.0.1         |* 30 November 2018    |                                                           |
 |                      |* 3.0.0         |* 15 April 2019       |                                                           |
 +----------------------+----------------+----------------------+-----------------------------------------------------------+