I have a shared hosting account which does not permit me to connect to my databases via mysqli or PDO. However, I can install WordPress and interact with the database via the various built-in forms. Using phpMyAdmin, I am able to create new tables within the WP database. I would like to access the tables I create via my own scripts rather than what WP provides. What wp files do I need to include in order to instantiate a new wpdb object in my script (using the values defined in wp-config.php)?