message: add info for reigster API
diff: @@ -66,6 +66,28 @@ export default function ApiRefTable({
  </table>
  </div>
  + <section>
  + <p>
  + <b className={typographyStyles.note}>Tip:</b>: What's happened to the
  + input after invoke register API:
  + </p>
  + </section>
  +
  + <CodeArea
  + rawData={`const { onChange, onBlur, name, ref } = register('firstName');
  +// include type check again field path with the name you have supplied.
  +
  +<input
  + onChange={onChange} // assign onChange event
  + onBlur={onBlur} // assign onBlur event
  + name={name} // assign name prop
  + ref={ref} // assign ref prop
  +/>
  +// same as above
  +<input {...register('firstName')} />
  +`}
  + />
  +
  <h2 className={typographyStyles.subTitle} id={"options"}>
  Options
  </h2>
  