[dotnet] Add dotnet projects and examples

+ Sitemap generator I created while learning the dispose pattern
+ Testing project for learning general C#

dotnet/testing/KlipsLibrary/Fruit.cs

@@ -0,0 +1,19 @@
+using System.Collections.ObjectModel;
+
+namespace KlipsLibrary;
+
+public class Fruit 
+{
+  public Fruit()
+  {
+    Name = "Default";
+  }
+
+  public Fruit(string name)
+  {
+    Name = name;
+  }
+  public string Name { get; set; }
+}
+
+public class Fruits : Collection<Fruit> { }