4.0 | Wiki/Requirements: minimum PHP version is now 7.2.0

Includes some readability updates.

Author: jrfnl

wiki/Requirements.md

@@ -1,6 +1,9 @@
-PHP_CodeSniffer requires PHP version 5.4.0 or greater, although individual sniffs may have additional requirements such as external applications and scripts. See the [Configuration Options](https://github.com/PHPCSStandards/PHP_CodeSniffer/wiki/Configuration-Options) manual page for a list of these requirements.
+PHP_CodeSniffer 4.x requires PHP 7.2.0 or greater.  
+_Prior to PHP_CodeSniffer 4.0.0, the minimum PHP requirement was 5.4.0._
 
 Additionally, PHP_CodeSniffer requires the following PHP extensions to be enabled:
 - Tokenizer: used by the core tokenizer to process PHP files
 - SimpleXML: used to process ruleset XML files
 - XMLWriter: used to create some report formats
+
+Individual sniffs may have additional requirements such as external applications and scripts. See the [Configuration Options](https://github.com/PHPCSStandards/PHP_CodeSniffer/wiki/Configuration-Options) manual page for a list of these requirements.