Added pt-PT locale.

Hello,

Please note that this adds the pt-PT locale according to the ortographic rules pre-2010.
The [new ortographic agreement](http://en.wikipedia.org/wiki/Portuguese_Language_Orthographic_Agreement_of_1990), was adopted in Portugal in 2010 and states that for example Contact should be `contato` instead of `contacto`. However, many people contest it and still use the old rules, it's a complicated matter.

For the purpose of this gem, the `pt_BR` locale is correct towards the new ortographic agreement, so I opted to submit `pt-PT` according to the old rules, as most people still use it.

Would you rather I'd submit according to the new rules?