introducing remote_monitors server that allows to defer "DOWN" message

...from remote monitor in case if the net kernel is restarted till the
start of the net kernel

this prevents the component that monitors the process on the other node from
multiple crashes during net_kernel restart window

Change-Id: I35d34876f3b4aad8a3835504d871d99191645b2b
Reviewed-on: http://review.couchbase.org/43621
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Tested-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
use remote_monitors in memcached_config_mgr and ns_ports_setup

so they don't crash during net_kernel restart

Change-Id: I6fa7573dea7ed587aa7ab191aca0778d315866d6
Reviewed-on: http://review.couchbase.org/43622
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Tested-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>