message: add shiftkey status
diff: @@ -23,6 +23,7 @@ const initialState = {
  distance: 0,
  down: false,
  first: true,
  + shiftKey: false,
  }
  function handlers(set, props = {}, args) {
  @@ -34,6 +35,7 @@ function handlers(set, props = {}, args) {
  return {
  ...newProps,
  event,
  + shiftKey: event.shiftKey,
  lastLocal: state.local,
  temp: temp || newProps.temp,
  }
  @@ -48,6 +50,7 @@ function handlers(set, props = {}, args) {
  target,
  args,
  lastLocal,
  + shiftKey: event.shiftKey,
  local: lastLocal,
  xy: [pageX, pageY],
  initial: [pageX, pageY],
  @@ -78,6 +81,7 @@ function handlers(set, props = {}, args) {
  ...state,
  event,
  time,
  + shiftKey: event.shiftKey,
  xy: [pageX, pageY],
  delta: [delta_x, delta_y],
  local: [
  