Coincident route segments should be merged

[chosak]

Multiple routes go along the same path, (e.g. multiple buses traveling along the same stretch of road) are often represented by different line segments on the map. This causes visual clutter and makes it harder to click on one particular segment of interest.

This is caused by route shapes as described in GTFS being slightly different. This occurs between routes in different GTFS datasets and even between routes in the same dataset. Often this is due to route shapes being collected via recorded GPS position, which may be slightly different from trip to trip.

Ideally, route segments could be "snapped to" road or track segments, ensuring that a user could see a single line or set of lines (see #7 and #13) for that location.