Take a unique ID for maps.

I want to be able to share this without giving away my data.

The page takes a query parameter map=<ID>, which says which data file to load.

If you load the page without a map ID, it makes up a random 8-digit hex string and uses that.

The no-selection view shows a link to the map.

elm.json

@@ -22,4 +22,4 @@
         "direct": {},
         "indirect": {}
     }
-}
+}