title: How to modify a property of a CMIS document using DotCMIS/OpenCMIS
body: <p>Let's say I have a document <code>doc</code> and I want to update its <code>barcode</code> metadata to <code>"01234"</code>.</p>
  
  <p>The document might have existing other properties, I don't want to lose them.<br>
  In case <code>doc</code> already has a <code>barcode</code>, it will be overwritten.</p>
  
  <p>How to do this with DotCMIS/OpenCMIS?</p>