SubTemplate: use SubTemplates for boxed content only

templates/AlbumButtonBox.php

@@ -6,7 +6,7 @@
  * Kabuki CMS (C) 2013-2016, Aaron van Geffen
  *****************************************************************************/
 
-class AlbumButtonBox extends SubTemplate
+class AlbumButtonBox extends Template
 {
 	private $buttons;
 
@@ -15,7 +15,7 @@ class AlbumButtonBox extends SubTemplate
 		$this->buttons = $buttons;
 	}
 
-	protected function html_content()
+	public function html_main()
 	{
 		echo '
 			<div class="album_button_box">';