/// <summary>
 /// Reads GeoJson and returns the feature collection.
 /// </summary>
 /// <param name="geoJson"></param>
 /// <returns></returns>
 public static FeatureCollection ToFeatureCollection(this string geoJson)
 {
     var jsonReader = new JsonTextReader(new StringReader(geoJson));
     return GeoJsonConverter.ReadFeatureCollection(jsonReader);
 }
 /// <summary>
 /// Reads GeoJson and returns the geometry.
 /// </summary>
 /// <param name="geoJson"></param>
 /// <returns></returns>
 public static Geometry ToGeometry(this string geoJson)
 {
     var jsonReader = new JsonTextReader(new StringReader(geoJson));
     return GeoJsonConverter.ReadGeometry(jsonReader);
 }