Initial data commit

Task/Hello-world-Graphical/C-sharp/hello-world-graphical-1.cs

@@ -0,0 +1,9 @@
+using System;
+using System.Windows.Forms;
+
+class Program {
+    static void Main(string[] args) {
+        Application.EnableVisualStyles(); //Optional.
+        MessageBox.Show("Goodbye, World!");
+    }
+}

Task/Hello-world-Graphical/C-sharp/hello-world-graphical-2.cs

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+using Gtk;
+using GtkSharp;
+
+public class GoodbyeWorld {
+  public static void Main(string[] args) {
+    Gtk.Window window = new Gtk.Window();
+    window.Title = "Goodbye, World";
+    window.DeleteEvent += delegate { Application.Quit(); };
+    window.ShowAll();
+    Application.Run();
+  }
+}