public function __construct()
 {
     $this->ci =& get_instance();
     $this->ci->load->config('pagseguro');
     PagSeguroLibrary::init();
     self::$config = $this->ci->config->item('pagseguro');
     self::$environment = self::$config['environment'];
     self::$email = self::$config[self::$environment]['pagseguroAccount'];
     self::$token = self::$config[self::$environment]['pagseguroToken'];
 }