The node does not support asynchronous object replication anymore, so it
does not need to have replicator worker, channel and `AddTask` function.
Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>
Implement Replicator service that performs background work to replicate
local object to remote nodes in the container. Replicator is going to be
used by Policer.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>