Show a polygon grouping of child areas

[vnugent]

What would you like to be able to do? Please describe. When viewing a large area I want to see what child areas belonging to this area. We can accomplish this by showing a polygon that including child area.

How important is this to you (Please pick one)

• Important

Todo:

• For a given area use its child area lat/long to calculate a polygon (see https://turfjs.org/docs/#polygon)
• Render the polygon geojson. See this example for how to construct a layer from geojson.