Add a utile EL function for formatting date and parsing date

<?taglib uri="http://www.zkoss.org/dsp/web/core" prefix="c" ?>
...
				
<template name="model">
	<listitem value="${each}">
		<listcell label="${each.version}"/>
		<listcell label="${c:formatDate(each.releaseDate, 'MMM dd, yyyy')}"/>
	</listitem>
</template>
...