Code review comment for lp:~widelands-dev/widelands/ferry

I played Calvission again fo about 4 hours gametime.
This was fine for the most parts, I found some of
the expected Issued: e.g. Buildings not attachted to roads dont get workers.
I found one Issue where ferries are not built.
But now I hit an seertion that should be reproducible, please check:
   https://www.magentacloud.de/share/tu4ayusx.k
   Unferry.wgf

If we really want this feature, we should get it in _now_ and fix such bugs
with seperate bugs. Otherwsie this Brnach will diverge more and more.

Lets get this decided soon.