Add geometry and distance to OsrmMatcher results

[nreinicke]

As described in #181 we don't return geometry and distance attributes from the OsrmMatcher.

OSRM does return a geometry object from their matching API and so we could tack on &geometries=geojson to our OSRM query and then parse the geometry that gets returned. If we get it back in geojson, it looks like they might give us a matched geometry for each point and so it might be as simple as just intelligently indexing into the coordinate array when we parse the matches but we should confirm that.