Dominican Republic IBAN parsing rules

Examples

    iex>  %IbanEx.Iban{
    ...>    country_code: "DO",
    ...>    check_digits: "28",
    ...>    bank_code: "BAGR",
    ...>    branch_code: nil,
    ...>    national_check: nil,
    ...>    account_number: "00000001212453611324"
    ...>  }
    ...>  |> IbanEx.Country.DO.to_string()
    "DO 28 BAGR 00000001212453611324"