func (w *Writer) RegisterCompressor(method uint16, comp Compressor) {
	if w.compressors == nil {
		w.compressors = make(map[uint16]Compressor)
	}
	w.compressors[method] = comp
}

// AddFS adds the files from fs.FS to the archive.
// It walks the directory tree starting at the root of the filesystem
// adding each file to the zip using deflate while maintaining the directory structure.
func (w *Writer) AddFS(fsys fs.FS) error {