Fix test depends of PHP version

tests/autoload.php

@@ -34,4 +34,8 @@ function dumpt()
     }
     $e = new Exception();
     echo "-------\nDump trace: \n" . $e->getTraceAsString() . "\n";
+}
+
+if(PHP_VERSION_ID > 50400) {
+    function php_gte_54() {}
 }

tests/cases/FenomTest.php

@@ -261,7 +261,7 @@ class FenomTest extends \Fenom\TestCase
     }
 
     /**
-     * @requires PHP >=5.4
+     * @requires function php_gte_54
      * @group pipe
      */
     public function testPipe()