title: Create custom feedback mode in jshell
body: <p>As from the documentation of /set feedback in jshell, there are following built-in modes:</p>
  
  <pre><code>verbose, normal, concise, and silent
  </code></pre>
  
  <p>Is it possible to create a feedback mode with the functionality of both concise and silent? Or we can change any one of the above mode?
  Or can we create our own custom feedback mode?</p>