Enabling Data Change Notifications for all nodes in cluster.
Two new interfaces are introduced ClusteredDataChangeListener and ClusteredDOMDataChangeListener and external applications will have to implement any of that interface,
if those applications want to listen to remote data change notifications.
Datastore registers listeners, which are instance of that interface, even on followers.
Change-Id: I0e29cdf2a08a2051de5fc8ce73b9ec8ac408e45b
Signed-off-by: Harman Singh <harmasin@cisco.com>
(cherry picked from commit
66a6b6f931af3fcd1ce61263c457304cfbdc2bb5)