使用Laravel 5配置文件向HTMLPurifier添加元素

I am using Mews HTML Purifier and have it working great!

However, there are a couple of HTML5 elements such as figure that I want to not be stripped out.

I have looked at the docs:

http://htmlpurifier.org/docs/enduser-customize.html

But cannot see any information on adding elements / the full config options for when using the Laravel config file.

I cant find information when setting up the config like this:

return [

'encoding'  => 'UTF-8',
'finalize'  => true,
'cachePath' => storage_path('app/purifier'),
'settings'  => [
    'default' => [
        'HTML.Doctype'             => 'XHTML 1.0 Strict',
        'HTML.Allowed'             => 'img[alt|src],ul,li,p,br,b,figure',
        'CSS.AllowedProperties'    => '',
        //'AutoFormat.AutoParagraph' => true,
        'AutoFormat.RemoveEmpty'   => true,
    ],
    'test'    => [
        'Attr.EnableID' => true
    ],
    "youtube" => [
        "HTML.SafeIframe"      => 'true',
        "URI.SafeIframeRegexp" => "%^(http://|https://|//)(www.youtube.com/embed/|player.vimeo.com/video/)%",
    ],
],

];

And then using it like:

Purifier::clean($request->content);