title: Started a branch too late, change the parent of my branch
body: <p>I have the following situation:</p>
  
  <pre><code>A---B---F---G---H (master)
       \
        \
         C---D---E (experimental)
  </code></pre>
  
  <p>My problem is that B is a very-very bad thing that shouldn't have happened on <code>master</code>. It belongs on <code>experimental</code>. However F---G---H are okay. Is there a way to make everything look like this:</p>
  
  <pre><code>A---F'---G'---H' (master)
  \
   \
    B---C---D---E (experiment)
  </code></pre>
  
  <p>I've read about rebase and stuff like that but the biggest problem is that <code>master</code> has been pushed to <code>origin</code>.</p>