Expose raw array for hexagon

[emeeks]

This is really useful if you want to, say, build a GeoJSON feature out of the hexagon coordinates, instead of just draw it directly to the screen. I use it for hexbinning on maps.

[mgold]

+1, unless there's already a way to do this that @emeeks missed (perhaps like this?). Hexbinning on GeoJSON is extremely useful.