rcld, protocol: Inform clients when the cluster structure has changed

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>
rcld, protocol: Do not allow RCL operation when cluster is being modified

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>
protocol: Retry synchronous requests if received *_DELAY

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>
rcld: Allow DRCL write cluster lock to wait for a while

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>
librcl: Fully restore client state after change in cluster structure

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>