Scaffold UI class

Ooui/UI.cs

@@ -0,0 +1,16 @@
+using System;
+
+namespace Ooui
+{
+    public static class UI
+    {
+        public static void Publish (string path, object value)
+        {
+        }
+
+        public static Element GetElementAtPath (string path)
+        {
+            throw new System.Collections.Generic.KeyNotFoundException ($"{path} does not exist");
+        }
+    }
+}