consumers not notified of messages if another consumer with selector/filter doesn't want it

  drain "q; {create:always, link:{selector:\"colour = 'red'\"}}" -f

  drain "q; {create:always, link:{selector:\"colour = 'blue'\"}}" -f

  for i in `seq 1 5`; do spout --content "red-$i" -P colour=red q; done
  for i in `seq 1 5`; do spout --content "blue-$i" -P colour=blue q; done
  for i in `seq 6 10`; do spout --content "red-$i" -P colour=red q; done