func (l *maxBytesReader) Close() error {
	return l.r.Close()
}

func copyValues(dst, src url.Values) {
	for k, vs := range src {
		dst[k] = append(dst[k], vs...)
	}
}

func parsePostForm(r *Request) (vs url.Values, err error) {
	if r.Body == nil {
		err = errors.New("missing form body")
		return
	}
	ct := r.Header.Get("Content-Type")
	// RFC 7231, section 3.1.1.5 - empty type