Don't initialize NickInfo's online state to true.

This went unnoticed for surprisingly long, but broke down badly
if you opened a query to someone on the WN list while they were
offline and the WN tab is open: A NickInfo gets on-demand initia-
lized, taken as online and the WN code starts doing periodical
WHOIS checks that end up spamming the FrontView with their "no
such server" responses ...