Testing the lower() function in the aggregate version.

>>>>templates/test.tpl
<?xml version="1.0" ?>
<opt:root>
{@vars is lower($vars)}
{@vars.v1}
{@vars.v2}
</opt:root>

>>>>data.php
$view->vars = array(
	'v1' => 'HI UNIVERSE',
	'v2' => 'Hi UnIvErSe'
);

>>>>expected.txt
OUTPUT

>>>>result.txt
hi universe
hi universe