[PATCH] Update C++17 library status docs

[Jonathan Wakely]

On 28/11/18 13:48 +0000, Jonathan Wakely wrote:
>	* doc/xml/manual/status_cxx2017.xml: Update C++17 status.
>	* doc/html/*: Regenerate.
>
>Committed to trunk.

Once the post-San Diego mailing is out I'll add a C++2a status page
too.