Fix exposed functions

Fix exposed functions

The Page util is supposed to intercept and enable exposed pages on
its own so that additional functions can be run in the generic __call__
Fix the code to check for the function argument correctly and use a
different argument than the standard cherrypy one for admin pages so
that we do actually land in the Page.__call__ all the time for those
pages.

Signed-off-by: Simo Sorce <simo@redhat.com>
Reviewed-by: Patrick Uiterwijk <puiterwijk@redhat.com>