Unresolved subdomain linls

Hi there,

Happy New Year.

While reviewing HTTP links I spotted a few subdomains that do not 
resolve anymore for various reasons.

Within the PHP.net mailing list page there is a link pointing 
lists.php.net. As this link is very relevant I would suggest redirecting 
it to the same page as the link is mentioned.
https://www.php.net/mailing-lists.php

Secondly there is a docs.php.net that is not relevant anymore. Which we 
could redirect to www.php.net for legacy purposed. For example; SO has 
links to the docs that we might not want to break 
(https://stackexchange.com/search?q=url%3adocs.php.net).

In my PR (https://github.com/php/web-php/pull/1731) I have changed those 
to www.php.net as they are compatible with the links on PHP.net itself.

Looking forwards to your thoughts.

-
Jordi Kroon