Documentation: Suggest using `fleetctl ssh` with `systemctl restart`
Documentation: Suggest using `fleetctl ssh` with `systemctl restart`

Partially addresses https://github.com/coreos/fleet/issues/975

dongsupark/fleet,dongsupark/fleet,coreos/fleet,jonboulle/fleet,endocode/fleet,dalbani/fleet,endocode/fleet,endocode/fleet,giantswarm/fleet,giantswarm/fleet,dalbani/fleet,dongsupark/fleet,jonboulle/fleet,dalbani/fleet,coreos/fleet,giantswarm/fleet,jonboulle/fleet,coreos/fleet