private function initConstant()
 {
     Config::$DEFAULT_SERVLET_NAME = "panel";
     Config::$CURRENT_LANGUAGE = Config::$DEFAULT_LANGUAGE = "fr";
     define("SERVLET_SUBFOLDER", "../servlet/");
     define("INCLUDE_SUBFOLDER", "includes/");
     define("PAGE_SUBFOLDER", "pages/");
     define("PAGE_ADD_SUBFOLDER", PAGE_SUBFOLDER . "add/");
     define("PAGE_EDIT_SUBFOLDER", PAGE_SUBFOLDER . "edit/");
     define("PAGE_LIST_SUBFOLDER", PAGE_SUBFOLDER . "list/");
 }