Adding new fields and home location methid to presence. Adding cleanup

(deleting all but one presence record) on logout so that they don't pile up.

OpenSim/Data/MySQL/MySQLGenericTableHandler.cs

@@ -177,6 +177,8 @@ namespace OpenSim.Data.MySQL
                 result.Add(row);
             }
 
+            reader.Close();
+
             CloseReaderCommand(cmd);
 
             return result.ToArray();