title: Getting null from simple expression
body: <p>I am using simple in camel for scripting languages.  I just need to set the body to null.</p>
  
  <p>I try this:</p>
  
  <pre>
  from("direct:start").setBody().simple("null");
  </pre>
  
  <p>and it sets the body to the literal string "null".</p>
  
  <p>If I do this:</p>
  
  <pre>
  from("direct:start").setBody().simple("${header.null}");
  </pre>
  
  <p>It works but seems a bit clunky.  Is there a simple way to say null?</p>