public function __construct()
 {
     parent::__construct();
     self::$library_assets = plugins_url('/includes/libraries/', dirname(__FILE__));
     self::$library_assets = self::strip_protocol(self::$library_assets);
     self::$plugin_assets = plugins_url('/assets/', dirname(__FILE__));
     self::$plugin_assets = self::strip_protocol(self::$plugin_assets);
     add_action('admin_init', array(__CLASS__, 'admin_init'));
     add_action('admin_menu', array(__CLASS__, 'admin_menu'));
     add_action('init', array(__CLASS__, 'init'));
     add_action('widgets_init', array(__CLASS__, 'widgets_init'));
     add_shortcode('wordpress_starter_shortcode', array(__CLASS__, 'wordpress_starter_shortcode'));
 }