title: how to return from task and mark task as being 'up-to-date'
body: <p>I would like to programmatically tell gradle to return from a task, for example:</p>
  
  <pre><code>task ('SetupLibs') &lt;&lt; {
  
      if (sometest)
         // how to tell gradle to return from this task 
         // because it is up-to-date 
  
      ...
  }
  </code></pre>
  
  <p>Is this possible in groovy?  how?</p>