Replace broken mailing list link with archive

Author: hugovk

README.rst

@@ -145,7 +145,8 @@ which can be found on PyPI.
 Questions?
 ----------
 
-There's a mailing list available for support on Google Groups,
-`html5lib-discuss <http://groups.google.com/group/html5lib-discuss>`_,
-though you may get a quicker response asking on IRC in `#whatwg on
-irc.freenode.net <http://wiki.whatwg.org/wiki/IRC>`_.
+Ask on IRC in `#whatwg on irc.freenode.net
+<http://wiki.whatwg.org/wiki/IRC>`_.
+
+Or browse the archives of the `html5lib-discuss mailing list 
+https://www.mail-archive.com/[email protected]/`_.