added support for grouping

src/presentation/Scripts/ScriptsTree/SelectableTree/INode.ts

@@ -0,0 +1,7 @@
+export interface INode {
+    readonly id: string;
+    readonly text: string;
+    readonly documentationUrls: ReadonlyArray<string>;
+    readonly children?: ReadonlyArray<INode>;
+    readonly selected: boolean;
+}