Fix php version check in installer, closes #1484925.

installer/check.php

@@ -37,10 +37,11 @@ echo '<input type="hidden" name="_step" value="' . ($RCI->configured ? 3 : 2) .
 <h3>Checking PHP version</h3>
 <?php
 
-if (phpversion() > 4.3) {
+define('MIN_PHP_VERSION', '5.2.0');
-    $RCI->pass('Version', 'PHP ' . phpversion() . ' detected');
+if (version_compare(PHP_VERSION, MIN_PHP_VERSION, '>=')) {
+    $RCI->pass('Version', 'PHP ' . PHP_VERSION . ' detected');
 } else {
-    $RCI->fail('Version', 'PHP Version 4.3.1 or greater is required');
+    $RCI->fail('Version', 'PHP Version ' . MIN_PHP_VERSION . ' or greater is required ' . PHP_VERSION . ' detected');
 }
 ?>