Changes to avoid issues with normalizing a phone number started with reserved +0 country code.

We'v faced an issue with normalizing a test phone number that starts with reserved +0 country code. The issue was with normalize() method that returned '0' as a normalized phone number in cases when we used "+00 000 000 000" number in our test cases. It's not a big dial to use another test number but from my point of view such wrong numbers should have not be recognized as a valid # as +0 zone is not assigned to a country.  
Based to the fact that E.164 does not use that zone and there is no plans to include it to this standard I suggest get rid of it and that's why I am sending this pull request.
But just in case I've only commented this part out to be able to return it back in the future if they assign this code to a country(but I believe it will not be a the nearest future because of bureaucracy, at least) And anyway it will be better to add this zone and an appropriate number format for it only when and if it happens.