View: method chaining, $return param in render(), .phtml suffix

 * - Use a .phtml suffix, as this is more kind to web editing tools such as Dreamweaver
 *   and allows us to do FilesMatch to deny access to them
 * - All methods return $this so these methods can be chained in controller methods, e.g.
 *   $this->loadView('listing.phtml')->set('howmany', 123)->render();
 * - Added to render() the $return flag. If true, the output is returned to the caller instead of
 *   printed to the output buffer; great for compsing email bodies, generating XML for internal use, etc.