MODIFIER STATE CHANGED

Fired when shift/ctrl/alt keys are pressed or released. Does not fire when an EditBox has keyboard focus. MODIFIER_STATE_CHANGED: key, down

Payload

 * key : string - "LSHIFT", "RSHIFT", "LCTRL", "RCTRL", "LALT", "RALT"
 * down : number - 1 for pressed, 0 for released