[Tagging] RFC: Seaway key - proposal for mapping ports

[stevea]

I think those are all great, Graeme, thank you for your crisp list.

There is also amenity=ferry_terminal; these wiki are already pointing to each other, though as I've said, a deeper treatment of how these do and do not overlap need some depth of treatment in the seaway key.

It's great to watch things progress forward here:  when so much else in the world seems stuck, OSM keeps growing!

SteveA