"Users Browsing this Forum" is unsorted (forumdisplay.php)

[Michael König]

...but I think most users would like to have it sorted by username

(forumdisplay.php:

	$forumusers = $DB_site->query("SELECT username, invisible, userid
						FROM user
						WHERE  inforum = $foruminfo[forumid]
							AND lastactivity > $datecut
							AND lastvisit <> lastactivity");

)