Add a method to flush the prim update buffers once a frame, since the timer

appear to be too slow to be useful, or fail too fire. I may remove the timers
as a consequence if this.

OpenSim/Framework/IClientAPI.cs

@@ -902,6 +902,8 @@ namespace OpenSim.Framework
                                         List<InventoryFolderBase> folders, bool fetchFolders,
                                         bool fetchItems);
 
+        void FlushPrimUpdates();
+
         void SendInventoryItemDetails(UUID ownerID, InventoryItemBase item);
 
         /// <summary>