title: git: put a branch in a subdirectory
body: <p>I have a git repository (at github.com) with two branches: master and gh-pages. I would like to have the gh-pages branch in a subdirectory, so that I don't need to switch branches every time.</p>
  
  <pre><code>repo/
      (content of the master branch)
      gh-pages/
              (content of the gh-pages branch)
  </code></pre>
  
  <p>Is that possible ?</p>