Create CircleLayers with a Physical Unit Radius

[seizler]

New Feature

Instead of screen units that change scale with the zoom of the map, please add the ability to define the circle radius in units such as meters or feet or miles or whatever. I need to encompass a certain radius around my features on the map and am having a hard time.

Why

This solves so much headache of converting a point feature geojson into a massive amount of coordinates to draw a fill layer perimiter.

[persidskiy]

@seizler Hi, a way to go here is to create a polygon with Turf and use the fill layer. https://mapbox.github.io/turf-swift/2.8.0/Structs/Polygon.html#/s:4Turf7PolygonV6center6radius8verticesACSo22CLLocationCoordinate2DV_SdSitcfc

// The radius is in meters here
let polygon = Polygon(center: coord, radius: 10000, vertices: 30)