Add JSONification of WebStats module. Adds a '?json' query parameter

to the fetch URL to return the data in JSON format. Also adds a simple
'sim.html' that uses JavaScript to display the JSON data. Not pretty
but an example.

OpenSim/Region/UserStatistics/IStatsReport.cs

@@ -34,5 +34,6 @@ namespace OpenSim.Region.UserStatistics
         string ReportName { get; }
         Hashtable ProcessModel(Hashtable pParams);
         string RenderView(Hashtable pModelResult);
+        string RenderJson(Hashtable pModelResult);
     }
 }