[PATCH v3] Add gdb.Value.format_string ()

[Eli Zaretskii]

> From: Marco Barisione <mbarisione@undo.io>
> Date: Mon, 18 Mar 2019 18:14:35 +0000
> Cc: gdb-patches@sourceware.org,
>  Eli Zaretskii <eliz@gnu.org>,
>  Tom Tromey <tom@tromey.com>
> 
> +when using the @code{format_string()} method or the @code{str()}
                        ^^^^^^^^^^^^^^^                      ^^^^^
This part is still not fixed.

Thanks.