reorganizing namespaces to put all the Data stuff into it's own namespace

/ dir structure.  This is coming in over a few changesets so consider trunk
broken for the next 30 minutes as these get pulled together.

OpenSim/Data/DataStoreBase.cs

@@ -0,0 +1,10 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace OpenSim.Framework.Data
+{
+    public abstract class DataStoreBase
+    {
+    }
+}