To explain the motivation a little bit, when VersionPress is installed, it rewrites the wpdb class
and adds its own logic into DB-manipulating methods. That is good for WordPress and all the 3rd party
plugins but not for VersionPress itself - it needs the raw query() functionality not to trigger
itself recursively. Now, the developers could call $wpdb->__wp_query() but that's ugly,
fragile and easy to forget. This proxy improves that.
(The PhpDoc API description below can be regenerated by ./wpdb-api-to-phpdoc.php.)