New servers.xml

Hi Janis,

I've been working with my fork of your script and noticed tonight that speedtest.net changed the format of servers.xml. It no longer contains the url2 attribute. I have made a change to my version to handle the change. I also have some additional command line parameters to help bound the test so it doesn't run indefinitely. Please let me know if you find any of it useful.

Regards,
Dave