Removed unused handler `ChangeLog`

~dev_rating/application/classes/Controller/Handler/ChangeLog.php

-<?php defined('SYSPATH') or die('No direct script access.');
-
-class Controller_Api_ChangeLog extends Controller_Handler
-{
-    public function action_index() {
-        return Model_System::getChangeLog();
-    }
-}
\ No newline at end of file