Add hhvm to travis tests, output code coverage as text
Merge pull request #13 from Jbekker/improve-travis-yml

Add hhvm to travis tests, output code coverage as text
Move all model classes to the Model namespace.
Split the AddressMetadataRepository into two repositories and a facade.
Update README.
Add a getAll() method to AddressFormatRepository.
Complete Model test coverage, fix order of assertEqualsTo params.
Update the bundled data.
Add the PIN postal code type (used by India).
Improve the AddressFormatRepository test.
Move the validator test to the correct namespace; cleanup.
Remove unused code from the subdivision validation method (as exposed by tests).
Fix a crash when the subdivision parent is null, expand test coverage.
Improve the SubdivisionRepository tests.
Move the shared repository translateDefinition() method to a trait, add test coverage.
AddressFormatRepositoryTest cleanup.
Fix a test fail in the SubdivisionRepositoryTest.
Grammar fixes.
Add a getAddressFormats method to the DataProvider, add tests coverage.
Rewrite the PostalFormatterTest, expand coverage.