Upgrade available Python SDL version to 3.0.0

Update XAPP-FRAME-PY module dependencies to use latest SDL version 3.0.0
(RIC-699) what contains support for SDL multi-namespace and sentinel based
DB capacity scaling features. Also Notification packing has been fixed in
SDL version 3.0.0 (RIC-795).
XAPP-FRAME API change: received SDL events are now returned as a list of
strings, earlier only one event of type string was possible to return.
This change applies to following XAPP-FRAME APIs: 'handle_events()' and
a callback function registered by the 'subscribe_channel()' call.
Bump XAPP-FRAME-PY version to 2.0.0.

Issue-ID: RIC-699

Signed-off-by: Timo Tietavainen <timo.tietavainen@nokia.com>
Change-Id: Ica3c89d5a47451874fbc5ccd9a6b021fd30f6a53
diff --git a/docs/release-notes.rst b/docs/release-notes.rst
index b2f0dcc..1c06fc1 100644
--- a/docs/release-notes.rst
+++ b/docs/release-notes.rst
@@ -11,6 +11,13 @@
 and this project adheres to `Semantic Versioning <http://semver.org/>`__.
 
 
+[2.0.0] - 2021-06-14
+--------------------
+* Add Xapp registration/deregistration APIs (`RIC-706 <https://jira.o-ran-sc.org/browse/RIC-706>`_)
+* Upgrade SDL 3.0.0 version, SDL scaling (`RIC-699 <https://jira.o-ran-sc.org/browse/RIC-699>`_)
+* Upgrade SDL 3.0.0 version, notification fix (`RIC-795 <https://jira.o-ran-sc.org/browse/RIC-795>`_)
+
+
 [1.6.0] - 2020-10-23
 --------------------
 * Add SDL wrapping API (`RIC-659 <https://jira.o-ran-sc.org/browse/RIC-659>`_)