I'm running into issue trying to sort the renderNav function. Here is the default code... 
function renderNav(PageArray $items) {
	// $out is where we store the markup we are creating in this function
	$out = '';
	// cycle through all the items
	foreach($items as $item) {
		// render markup for each navigation item as an <li>
		if($item->id == wire('page')->id) {
			// if current item is the same as the page being viewed, add a "current" class to it
			$out .= "<li class='current'>";
		} else {
			// otherwise just a regular list item
			$out .= "<li>";
		}
		// markup for the link
		$out .= "<a href='$item->url'>$item->title</a>";
		// if the item has summary text, include that too
		if($item->summary) $out .= "<div class='summary'>$item->summary</div>";
		// close the list item
		$out .= "</li>";
	}
	// if output was generated above, wrap it in a <ul>
	if($out) $out = "<ul class='nav'>$out</ul>\n";
	// return the markup we generated above
	return $out;
}
I'm wanting it to order the pages from newest to oldest. The code above list oldest to newest. Can anyone help me out with this?