Move persistence clases to persistence package.

mindplot/src/main/javascript/model/INodeModel.js

@@ -82,6 +82,15 @@ mindplot.model.INodeModel = new Class({
         return result;
     },
 
+    setImageUrl:function(url) {
+        this.putProperty('imageUrl', url);
+
+    },
+
+    getImageUrl:function() {
+        return this.getProperty('imageUrl');
+    },
+
     getMindmap  : function() {
         return this._mindmap;
     },

mindplot/src/main/javascript/model/Mindmap.js

@@ -22,7 +22,7 @@ mindplot.model.Mindmap = new Class({
             this._branches = [];
             this._description = null;
             this._relationships = [];
-            this._version = $defined(version) ? version : mindplot.ModelCodeName.TANGO;
+            this._version = $defined(version) ? version : mindplot.persistence.ModelCodeName.TANGO;
             this._id = id;
         },