City names are now disambiguated by a two-letter country code. This
commit handles almost everything needed to make this transition. Main
next steps are fixing up map edits automatically and making the city
picker UI understand the extra level of hierarchy.
A little bit of fallout: lakeslice gridlocks again; this regression is
actually from the recent traffic signal changes, but I'm just now
regenerating everything. Will fix soon.
Also give living_streets in Krakow shoulders, so foot routing works
better there.
Now regenerate everything. Actually messes up routing for Trumpington;
71 cancelled trips up to 101. And have to intervene to keep lakeslice
not gridlocking, as usual.
widgetry, geom, and abstutil may wind up on crates.io in some form to
let other projects use widgetry. abstio has A/B Street-specific tricks
for reading data on native/web. Note widgetry still depends on abstio,
will figure out how to clean that up next.