Notably, both Dresden Hbf and Dresden-Neustadt fall into this category,
and these should definitely be found.

before, slashes in station names could not be handled, as they are split
during parsing of the incoming request to see if the last (really the
second) part was /gleis or /tracks.

Now, instead the list is un-snoc'd, and then if the last part is not one
that requires special handling, we fall through to treating it as a
station name.

Cassava's (.!) throws exceptions on missing fields even if there's a
reasonable default value. Shouldn't do that anymore.