protocol: Remove BROKEN request, it is replaced by LEAVE

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>
protocol: Do not send reply if error was RCL_NETWORK_ERROR

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>
rcld, protocol: Do not increase sequence number if reply was not sent

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>
protocol: Retry request if node is responding to NULL

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