title: git repository - copy changed files to new directory
body: <ol>
  <li>I have <code>git-repository</code> for web-project with several files in several directories.</li>
  <li>I make changes in some files, <code>commit</code> them.</li>
  <li>Now I need <code>diff</code> current updated state and state before update and <strong>copy all files (with proper directories) that were changed into separate directory (out of git) to load them on server.</strong></li>
  </ol>
  
  <p>How can I do the 3-d part?</p>