permit setting departPos and arrivalPos from mapMatching

[namdre]

new duarouter option --mapmatch.edgepos which replaces default departPos and default arrivalPos by the nearest offset on the matched edges.

The new option would be incompatible with --mapmatch.junctions

should also be supported by sumo eventually (#2182)

[namdre]

@angelobanse The relevant code is in RORouteHandler::parseGeoEdges, it should be fairly easy to add an output parameter and use this to override departPos, arrivalPos depending on the departPosProcedure of the vehicle.