phpcs is listed on packagist, no vcs entry needed

No vcs-entry needed for composer.json: phpcs is listed on [packagist.org](https://packagist.org/packages/squizlabs/php_codesniffer).

Question on this: why did you not list your standard on packagist.org?
That way you can extend reach and phpcs can call sniffs/ standards from path anyway.