Make autoloader for new names PSR-0 compliant

lib/PhpParser/Autoloader.php

@@ -24,7 +24,7 @@ class Autoloader
      */
     static public function autoload($class) {
         if (0 === strpos($class, 'PhpParser\\')) {
-            $fileName = dirname(__DIR__) . '/' . rtrim(strtr($class, '\\', '/'), '_') . '.php';
+            $fileName = dirname(__DIR__) . '/' . strtr($class, '\\', '/') . '.php';
             if (file_exists($fileName)) {
                 require $fileName;
             }