Warn if sending message to down network.
Warn if sending message to down network.

jech/babeld,tcatm/babeld,woniullb/babeld,wlanslovenija/babeld,Gwendocg/babeldToS,jech/babeld,boutier/babeld,dtaht/babeld-shortrtt-metrics,sudomesh/babeld,Gwendocg/babeldToS,Drooids/babeld,wlanslovenija/babeld