/**
  * @param string $key
  * @param mixed $value
  * @return bool
  */
 public static function set($key, $value)
 {
     if (!self::load()) {
         return false;
     }
     self::$changed = true;
     self::$cache['updated'] = time();
     self::$cache['data'][$key] = $value;
     return true;
 }