title: How to declare an Optional type in C#?
body: <p>Java 8 has <code>Optional&lt;T&gt;</code> which is nice way to declare optional types as described <a href="http://docs.oracle.com/javase/8/docs/api/java/util/Optional.html" rel="noreferrer">here</a>. 
  Is there an equivalent way to that in C# ?</p>