Review all sniffs for compatibility with PHPCS >= 4.0

Development on PHPCS 4.x has started a while back.

While there is no timeline known for when it will be ready/released, some (breaking) changes which PHPCS 4.x will contain are already known.

Notable changes as known at the time of writing this:
* The minimum supported PHP version is slated to become PHP 7.2.
* Support for the PEAR installation method will be removed.
* Support for JS and CSS sniffs will be removed.
* Support for the "old-style" ignore annotations, like `@codingStandardsIgnoreLine` will be removed. These were deprecated in PHPCS 3.2.0.
* Support for the "old-style" array properties in rulesets, where array items would be passed via a comma separated value instead of as individual items. This was deprecated in PHPCS 3.3.0.
* Deprecated tokens will be removed, most notably `T_ARRAY_HINT` and `T_RETURN_TYPE` which were both deprecated in PHPCS 3.3.0.

I expect most of this won't have much effect on the sniffs in VIPCS. If/when more changes become known, I will update the above list.

However, a decision is needed about the future of the sniffs which look at JS/CSS code. There is no urgency (yet), but I'm opening this issue now to raise awareness and open the discussion about this.

Non sono indicati file o test specifici. Inizia esaminando tutti gli sniffs VIPCS alla luce delle modifiche elencate di PHPCS 4.x, quindi esamina la discussione sulla rimozione o il mantenimento degli sniffs JavaScript e CSS. Il lavoro sarà considerato completato quando saranno documentati i risultati sulla compatibilità e sarà stata presa una decisione sugli sniffs interessati.

Scritto dal modello di indicizzazione a partire dal testo della issue.