message: Update changelog for 1.4.0
diff: +## [1.4.0] - 03-Jun-2019
  +* Add callback to useEffect deps to allow update of hotkeys when callback changes
  +* This also fixes the stale state bug
  +
  ## [1.3.4] - 11-May-2019
  * Bump hotkeys version to 3.6.8
  