Syntax: %bUNLINK [nickname [password]]%b

This command will unlink your nickname from your current
link. Or, if [nickname [password]] is specified, it will
unlink [nickname] from it's current link. When you unlink,
the access list of the master of the link will be copied
to your own. Memos, however, are not copied. If you are
unlinking the master nickname, the next nickname in the
link will become the new master.

Example:
        %b/msg %N UNLINK%b
          Unlinks your nickname from your link.

        %b/msg %N UNLINK CoolGuy CoolGuysPassword%b
          Unlinks "CoolGuy" from whatever link he
          was in.
