title: reload compare editor input
body: <p>I have a CompareEditorInput shown in CompareEditor, it compares textual data. I need to reload CompareEditorInput when it is changed outside of CompareEditor.</p>
  
  <ol>
  <li>Open compare editor (CompareUI.openCompareEditor(input))</li>
  <li>Compare input is changed (ISteramContentAccessor.getContents() returns changed content)</li>
  <li>Tell opened compare editor to reload CompareEditorInput &lt;- needs to be implemented.</li>
  </ol>