public HandlerRegistration addShowRangeHandler(ShowRangeHandler<UTCDate> handler) {
        return addHandler(handler, ShowRangeEvent.getType());
    }
Creates a new date picker.

@param monthAndYearSelector the month selector
@param view                 the view
@param model                the model
stroom-core-client-widget/src/main/java/stroom/widget/datepicker/client/CustomDatePicker.java