Updated PHP version for PHP7.2+

Removed PHP5 (no longer supported)
Renamed PHP7 to PHP - consistent with other kata
Added the same helpers as other PHP Kata
Updated the code to PHP7.2+ standard
Didn't change GildedRose updateQuality method
Updated GildedRoseTest (still failing)
Added ApprovalTest (passing)
- same text file as texttests / ThirtyDays / stdout.gr (only renamed).

php/src/Item.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+namespace GildedRose;
+
+final class Item
+{
+    /**
+     * @var string
+     */
+    public $name;
+
+    /**
+     * @var int
+     */
+    public $sell_in;
+
+    /**
+     * @var int
+     */
+    public $quality;
+
+    public function __construct(string $name, int $sell_in, int $quality)
+    {
+        $this->name = $name;
+        $this->sell_in = $sell_in;
+        $this->quality = $quality;
+    }
+
+    public function __toString(): string
+    {
+        return "{$this->name}, {$this->sell_in}, {$this->quality}";
+    }
+}