Feature request for adding a Properties map inside the FeatureCollection type so that various metadata can be saved inside while passing the "model" around within the program.
https://godoc.org/github.com/paulmach/orb/geojson#FeatureCollection

I understand the GeoJSON standard considers it a "may" feature, but a richer/more expressive in-memory representative would be pretty handy. Also, the marshaller should also serialize it consistent with the Feature implementation, so JavaScript code (e.g in a Mapbox GL JS HTML page) can also access it easily.

Thanks
Siddharth