Network Tests Updated

I have revamped the network tests as agreed at a dteam meeting a couple of weeks ago. The tests now involve copying files from the Tier-1 to the local SE, copying the files from the local SE to the WN and copying them back to all SEs. There is quite a high failure rate. Some of this is transfer/catalogue/info failures and some of it is attempts to get more reliable results by using different timings and asking for consistency between them. Sometimes the times vary wildly with smaller files taking longer etc. I am sure there is more to be done.