* Stop warnings about non existent scene presences/entities being removed on client log off

* This is being done by preventing close from being called twice on child agent closure (nres which would have been thrown are being swallowed).  
* However, it should be possible to do much better cleanup on this code in the future

OpenSim/Framework/Communications/Cache/UserProfileCacheService.cs

@@ -86,7 +86,9 @@ namespace OpenSim.Framework.Communications.Cache
                 }
             }
 
-            m_log.ErrorFormat("[USER CACHE]: Tried to remove the profile of user {0}, but this was not in the scene", userId);
+            m_log.WarnFormat(
+                "[USER CACHE]: Tried to remove the profile of user {0}, but this was not in the scene", userId);
+            
             return false;
         }