Use specified country_code in phone number when normalizing

[espen]

fixes issue #22

[espen]

Was supposed to create a new pull request for the last commit but since it is so minor I'll just let it be unless it bothers you.

[joost]

I changed it a bit. You can now force a country_code using:

PhonyRails.normalize_number('+4790909090', :country_code => 'SE').should eql('464790909090')

Or specify a default_country_code and it would not overwrite a given country_code:

PhonyRails.normalize_number('+4790909090', :default_country_code => 'SE').should eql('4790909090') # SE = +46

[espen]

Makes sense. Perhaps use default_country_code in String.phony_formatted?

Current result:
"+4790909090".phony_formatted(:normalize => "SE", :format => :international, :spaces => '')
=> "+464790909090"