fix view history of maps

mindplot/src/main/javascript/LocalStorageManager.js

@@ -37,6 +37,7 @@ mindplot.LocalStorageManager = new Class({
             if (xml == null || this.forceLoad) {
                 $.ajax({
                     url: this.documentUrl.replace("{id}", mapId),
+                    headers:{"Content-Type":"text/plain","Accept":"application/xml"},
                     type:'get',
                     dataType: "text",
                     async: false,

wise-webapp/src/main/webapp/jsp/mindmapEditor.jsp

@@ -50,7 +50,7 @@
                 );
             </c:if>
             <c:if test="${memoryPersistence || readOnlyMode}">
-                    options.persistenceManager = new mindplot.LocalStorageManager("c/restful/maps/{id}${hid!=null?'/':''}${hid!=null?hid:''}/document/xml${principal!=null?'':'-pub'}",true);
+                options.persistenceManager = new mindplot.LocalStorageManager("c/restful/maps/{id}${hid!=null?'/':''}${hid!=null?hid:''}/document/xml${principal!=null?'':'-pub'}",true);
             </c:if>
 
                 var userOptions = ${mindmap.properties};