[OSM-dev] Changed unsurfaced style in osm.xml

[Nick Whitelegg]

Hello Artem and Steve (and anyone else interested in this),

I've updated osm.xml to show ways tagged as "unsurfaced" or "track" in dashed 
white lines, the typical "track" representation on streetmaps. These are now 
distinguished from highway=byway (byways - a type of official right of way) 
which remain in yellow dashed lines.

This is because "unsurfaced" can encompass residential roads with no made-up 
surface, and a style appropriate for a right of way (formerly, 
highway=unsurfaced was rendered the same as highway=byway) is not appropriate 
in these cases.

Nick