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/.gitignore

@@ -0,0 +1,6 @@
+/.idea 
+/report.xml 
+/.phpstorm.meta.php 
+/.phpunit.result.cache
+/build
+/vendor