conf.py: Prevent traceback if server address is an IPv6 address.
conf.py: Prevent traceback if server address is an IPv6 address.

Signed-off-by: James McCoy <91ae71a1168cea0b65ac9975da69d5a7753116be@users.sourceforge.net>

frumiousbandersnatch/supybot-code,ProgVal/Limnoria-test,jeffmahoney/supybot,ProgVal/Limnoria-test,Ban3/Limnoria,Ban3/Limnoria,haxwithaxe/supybot,buildbot/supybot