Name nameless stops from their stop_area relation

As documented here: https://wiki.openstreetmap.org/wiki/Tag:public_transport%3Dstop_position
and here: https://wiki.openstreetmap.org/wiki/Tag:highway%3Dbus_stop
the stop_area can carry a name valid for its members.

I implemented using the stop_area name for recognised stop members without a name. I think this was intended to reduce the need for double tagging stop_areas and their members.
 
Its just about to show names, and make their absence appear less as an error in data. 

Please review / comment.