Dashboard completed. Demo files added

src/layout/service/NodeService.js

@@ -0,0 +1,11 @@
+export default class NodeService {
+
+    getTreeTableNodes() {
+        return fetch('data/treetablenodes.json').then(res => res.json()).then(d => d.root);
+    }
+
+    getTreeNodes() {
+        return fetch('data/treenodes.json').then(res => res.json()).then(d => d.root);
+    }
+    
+}