UDDI OPML now much quicker

The UDDI OPML list is now being cached in memory and refreshed every three minutes on a background thread. Unless the AppDomain recycles, the responses should be instantaneous now, unless you are doing a query on categories, because that needs to happen live because I don't want to cache each and every request combination on our server here and have it take up too much memory for this demo.

I looked at IBM's UDDI service yesterday and at least the web interface is by several magnitudes quicker (from here). I should probably play with their service a little to improve response times. ( ... just did, IBM and SAP aren't any faster)