private function __construct()
 {
     include 'inc/wp-remote-posts-data-api.php';
     include 'inc/wp-remote-posts-rewrite.php';
     include 'inc/wp-remote-posts-templates.php';
     include 'inc/models/wp-remote-posts-item.php';
     WP_Remote_Posts_Rewrite::register();
     WP_Remote_Posts_Templates::register();
 }
 public static function register()
 {
     if (self::$instance == null) {
         self::$instance = new WP_Remote_Posts_Rewrite();
     }
 }