Allow AbstractClientActor generation to start from non-zero
This adds the ability to override the initial generation seeded
into persistence. The requested generation is controlled via
system properties on a per-client-type basis:
org.opendaylight.controller.cluster.access.client.initial.generation.datastore-operational = 500
This is useful during bringup of a zombie node, which lost all
of its persistence, for example during recovery from backup.
JIRA: CONTROLLER-1626
Change-Id: If32487fedcb5b6b39551a3359c069df940a6a725
Signed-off-by: Robert Varga <robert.varga@pantheon.tech>
(cherry picked from commit
2be60a19ed99fe7d33a24f7db8af3510f7ea835f)
(cherry picked from commit
67afa21bc175d7a6ebd3df7607644d4c9326710e)