Revert "Added request.Proxy=null everywhere, as discussed in http://stackoverflow.com/questions/2519655/httpwebrequest-is-extremely-slow."

But the patch is here, in case anyone wants to try it.

This reverts commit 531edd51d8.

OpenSim/Services/Connectors/SimianGrid/SimianGridMaptileModule.cs

@@ -212,7 +212,6 @@ namespace OpenSim.Region.OptionalModules.Simian
                 HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(m_serverUrl);
                 request.Timeout = 20000;
                 request.ReadWriteTimeout = 5000;
-                request.Proxy = null;
 
                 using (HttpWebResponse response = MultipartForm.Post(request, postParameters))
                 {