This makes sure that all polygon rings have at least 4 coordinates, and that the first coordinate and last coordinate in a ring are equal. Fixes cases where a polygon is oversimplified to a single point/line, such as in https://github.com/Turfjs/turf/issues/247
This makes sure that all polygon rings have at least 4 coordinates, and that the first coordinate and last coordinate in a ring are equal. Fixes cases where a polygon is oversimplified to a single point/line, such as in https://github.com/Turfjs/turf/issues/247