title: How to get $CHANGES from upstream Jenkins job?
body: <p>At the moment I trigger a downstream build the $CHANGES variable is empty (though I have changes, once build is completed changes are displayed.</p>
  
  <p>I'm trying to pass this variable to the downstream job as one of the predefined parameters and no wonder it receives nothing.</p>
  
  <p>How can I pass upstream changes to a downstream project?</p>