Update tree link heartbeat when enabling a tree link
Update tree link heartbeat when enabling a tree link

Do not forward tree create messages until the node has at least one tree link active, otherwise this will create loops in the tree

ninuxorg/olsrd,brabander/olsr,acinonyx/olsrd,diogomg/olsrd-binary-heap,duydb2/olsr,servalproject/olsr,brabander/olsr,zioproto/olsrd,brabander/olsr,ninuxorg/olsrd,diogomg/olsrd-binary-heap,servalproject/olsr,diogomg/olsrd,nolith/olsrd,tdz/olsrd,sebkur/olsrd,tdz/olsrd,tdz/olsrd,zioproto/olsrd,cholin/olsrd,duydb2/olsr,acinonyx/olsrd,zioproto/olsrd,zioproto/olsrd,nolith/olsrd,ninuxorg/olsrd,zioproto/olsrd,diogomg/olsrd-binary-heap,tdz/olsrd,sebkur/olsrd,diogomg/olsrd-binary-heap,cholin/olsrd,sebkur/olsrd,brabander/olsr,duydb2/olsr,acinonyx/olsrd,diogomg/olsrd-binary-heap,duydb2/olsr,duydb2/olsr,acinonyx/olsrd,ninuxorg/olsrd,cholin/olsrd,nolith/olsrd,servalproject/olsr,servalproject/olsr,acinonyx/olsrd,sebkur/olsrd,diogomg/olsrd,nolith/olsrd,servalproject/olsr,diogomg/olsrd,diogomg/olsrd-binary-heap,duydb2/olsr,diogomg/olsrd,diogomg/olsrd,duydb2/olsr,diogomg/olsrd-binary-heap,nolith/olsrd,duydb2/olsr,tdz/olsrd,cholin/olsrd,servalproject/olsr,sebkur/olsrd,cholin/olsrd,diogomg/olsrd,diogomg/olsrd,sebkur/olsrd,ninuxorg/olsrd