Spain IBAN parsing rules

Examples

    iex>  %IbanEx.Iban{
    ...>    country_code: "ES",
    ...>    check_digits: "91",
    ...>    bank_code: "2100",
    ...>    branch_code: "0418",
    ...>    national_check: "45",
    ...>    account_number: "0200051332"
    ...>  }
    ...>  |> IbanEx.Country.ES.to_string()
    "ES 91 2100 0418 45 0200051332"