title: Retrolambda - Jack is required to support java 8 - warning fix
body: <p>Is there a way to disable warning about</p>
  
  <blockquote>
    <p>Jack is required to support java 8 language features.</p>
  </blockquote>
  
  <p>while using Retrolambda?</p>
  
  <p>I don't want jack support for now since it doesn't yet compile our project. </p>