func ToString(id ID) (string, error) {
	if id == 0 {
		return "null", nil
	}
	hash, err := hash.Encode(id)
	if err != nil {
		return "", err
	}
	return string(hash), nil
}
ToString returns a new hash from given ID by using the hasher or an error if it couldn't encode the ID.
If ID is 0, "null" will be returned.
package hide
func FromString(id string) (ID, error) {
	return hash.Decode([]byte(id))
}