Added basic category chooser UI

src/render/CategoryChooser.tsx

@@ -0,0 +1,15 @@
+import * as React from "react";
+import * as ReactDOM from "react-dom";
+import CategoryChooserComponent from "../components/CategoryChooserComponent";
+
+class CategoryChooser {
+
+    constructor(element: Element) {
+        ReactDOM.render(
+            <CategoryChooserComponent/>,
+            element
+        );
+    }
+}
+
+export default CategoryChooser;