Support for route_master

[Skippern]

Would like to see support for route_master relations like this; http://www.openstreetmap.org/browse/relation/4605600

The one in the example should consist of 3-4 relations forming parts of the same extremely long highway, the Brazilian BR-101 which spans from Recife in north of Brazil to Rio Grande in the south of Brazil.

Supporting this correctly would enable us to see if the master relation is correctly built, and check the integrity of each of the member relations.

[pyrog]

Same for type=superroute. Example: GTJ à cheval

In practice, could you do that for any relations that contain relations ?

See also:

• Relation:superroute.
• On Waymarked Trails:
  • GTJ à cheval.
  • EuroVelo 6 a super route of super routes.
• In maps/riding.py#L29 there is a filter expression in a SQL query.