Start of merging changes from Google's v5.8

Unit Tests do fail, from a quick look, it appears because it's using the
test data, but the emergency numbers are stored only in the ShortNumber
data.
Update composer.json to use this branch as 5.8-dev
Incorrect functional call in ShortNumberInfo

Added carrierSpecific to the build process, and rebuilt data files.

Unit tests still fail
Remove unit test that isn't in the Google Code
Update isNumberPossibleForDesc and isNumberMatchingDesc to use Matcher
Pass type hinting in PHPDoc instead of the function
Update README
Merge pull request #6 from giggsey/google_v5.8

v5.8