Monitored machines:
Currently, we can only monitor AIX, Linux and SunOS.  You can extend getstats
to cater for other OSes.

Graph expiry:
You should set your server to expire the .gif files in the graphs directory 
in 5 minutes.  Apache users can use the supplied .htaccess file in conjunction
with mod_expires, but IIS users may have a bitmore of a problem.

