minor: Assign names to the different SmartThreadPools for debugging purposes.

A different approach to the patch in http://opensimulator.org/mantis/view.php?id=6462
that doesn't involve further forking of SmartThreadPool

OpenSim/Framework/Util.cs

@@ -1640,6 +1640,7 @@ namespace OpenSim.Framework
                 throw new InvalidOperationException("SmartThreadPool is already initialized");
 
             m_ThreadPool = new SmartThreadPool(2000, maxThreads, 2);
+            m_ThreadPool.Name = "Util";
         }
 
         public static int FireAndForgetCount()

OpenSim/Region/ScriptEngine/XEngine/XEngine.cs

@@ -1487,6 +1487,7 @@ namespace OpenSim.Region.ScriptEngine.XEngine
             startInfo.StartSuspended = true;
 
             m_ThreadPool = new SmartThreadPool(startInfo);
+            m_ThreadPool.Name = "XEngine";
         }
 
         //