`#to_money` is not working when the symbol currency does not match with `Monetize::Parser::CURRENCY_SYMBOLS`

[Albertc]

With currencies like ARS that have the same symbol than dollar ( '$' ) when running for example

"13,532,000.00 ARS".to_money

the returned value is

#<Money fractional:1353200000 currency:USD>

[Albertc]

As I can see, this is caused by this line:

  `computed_currency = nil unless Monetize::Parser::CURRENCY_SYMBOLS.value?(computed_currency)`

because computed_currency is not in the list