Add a __toString() method to the default Currency class.
Add a method for converting the price to another currency, expand README.
Fix the stripping of trailing zeroes to ignore non-decimal numbers.
Rename decimals to fraction digits, to match naming in other places (currency classes in other languages, NumberFormatter, Symfony).
Add translation support for currency names and symbols.

- Rename currency.yml to currencies.yml
- Re-export currencies.yml from the ISO and CLDR data.
- Make sure that the symbols and names in currencies.yml are en_US.
- Update README.
Add the script that generates the yaml data.
Remove the zone yml files and David from the maintainers, that will be added to a new tax library.
Fix currency ordering in currencies.yml, remove a few 'special currencies' that were accidentally added, update export script.
Use getFractionDigits instead of getDecimals in round
Merge pull request #5 from pcambra/master

Use getFractionDigits instead of getDecimals in round
Disallow negative precision
Merge pull request #7 from pcambra/Disallow_negative_precision

Disallow negative precision
Remove the currency handling, depend on commerceguys/intl.