Note when other hunters shot the duck first

[henke37]

Sometimes it can be a matter of milliseconds which hunter gets to shot a duck. The other(s) end up with a ill fitting message of there not being any duck to shoot.

It would be more polished if there was a customized message for this scenario.

[paris-ci]

Actually, there is already such a message, but I fixed the race-condition it was hiding, so it triggered exactly 0 times in the history x)

Keeping that open until I can figure a proper solution to implement this without race conditions