unselect a selected event on event click

The default behavior corresponds to the typical file manager behavior - clicking an event selects it, clicking another event changes the selection to the new event, Ctrl+click is required to unselected an event.

You can add the following code to onEventClick to unselect events on click:

dp.onEventClick = function(args) {
    if (dp.multiselect.isSelected(args.e)) {
        dp.multiselect.remove(args.e);
        args.preventDefault();
    }
};