code: public function getMrtg($period,$type)
      {
          return json_decode(self::getClient()->getMrtg($this->getDomain(),$period,$type));
      }
docs: Get MRTG
  Ajout by @Thibautg16 le 11/11/2013
  
  @throws Exception\ServerException
  @throws \Ovh\Common\Exception\BadMethodCallException
  @return array of strings