document config options

[morganherlocker]

We have a high level description of the config file, and we have an example config:

• https://github.com/sharedstreets/mobility-metrics#configuration
• https://github.com/sharedstreets/mobility-metrics/blob/master/example/example.json

I think the config is now gaining enough options that it would be helpful to add a section in the readme describing each option in more detail.

[morganherlocker]

Added the following section to the readme in v4.0:

Options

• boundary
  • a GeoJSON bounding box array used for downloading the street network for matching
• center
  • default map center represented as a coordinate array
• zoom
  • default map zoom level
• privacyMinimum
  • minimum unique record count for geographic trip volumes and origin destination flows
• lost
  • maximum number of days without status change before vehicles are permanently lost
• summary
  • enabled or disabled metrics in summary UI
• providers
  • list of providers to query
  • type
    • "local" for data off disk or "mds" for data off MDS provider API
  • trips
    • URI of trip data
  • status_changes
    • URI of status change event feed
  • token
    • token for MDS API; blank if local
  • enabled
    • true or false
• zones
  • optional GeoJSON FeatureCollection of Polygons and/or MultiPolygon with a unique property named id