/* 
 * Return a new Imlib2::Polygon
 *
 * Examples:
 *   poly = Imlib2::Polygon.new
 *
 *   points = [[10, 10], [20, 30], [15, 8], [6, 3], [12, 2]]
 *   poly = Imlib2::Polygon.new *points
 *
 */
VALUE poly_new(int argc, VALUE *argv, VALUE klass) {