Lithuanian IBAN parsing rules

Examples

    iex>  %IbanEx.Iban{
    ...>    country_code: "LT",
    ...>    check_digits: "12",
    ...>    bank_code: "10000",
    ...>    branch_code: nil,
    ...>    national_check: nil,
    ...>    account_number: "11101001000"
    ...>  }
    ...>  |> IbanEx.Country.LT.to_string()
    "LT 12 10000 11101001000"