ZK DataBinding support client callback function after some command triggered

<zk>
Please click the "Click" button, you should see "clicked !!" in the textarea
	<div viewModel="@id('vm') @init('org.zkoss.zktest.test2.F80_ZK_2614_VM')">
		<button label="Click" onClick="@command('clickable')"/>
	</div>
	<script>
	zk.afterMount(function () {
		var binder = zk.Widget.$(jq("@button")).$binder();
		binder.after('clickable', function () {
			zk.log('clicked !!');
		});
	});
	</script>
</zk>