OPTIONAL
SYNOPSIS
        int set_is_wizard(object ob, int n)
DESCRIPTION
        Change object ob's wizardhood flag.
        If n is 0, it is cleared, if n is, it is set, if n is -1 the
        current status is reported. The return value is always the old
        value of the flag. Using this function sets a flag in the
        parser, that affects permissions for dumpallobj etc, which are
        by default free for every user.
HISTORY
        Since 3.2.7 this efun is optional.