Improvements to viewonline.php

The viewonline page gives the "Forum Location" for each reported session, but the data in this field defaults to "Index" for any page that is not specifically coded in viewonline.php.

This makes it look as if a lot of users are hitting the index page when in fact they are somewhere on another page.

I have created a patch which changes the default value to "Unrecognised Page"
The patch additionally displays (to admins only) the actual page URI from the sessions table, which is much more interesting.