default dbo tostring

src/Business/lu-webapi-crud-business.js

                 Business.dataAccess = dataAccess;
 
                 Business.defaultDbo = {
-                    id: null
+                    id: null,
+                    toString: function()
+                    {
+                        return this.id;
+                    }
                 };
 
                 Business.extendDeep = function extendDeep(dst) {