title: I need to pop up and trash away a "middle" commit in my master branch. How can I do it?
body: <p>For example, in the following master branch, I need to trash just the commit af5c7bf16e6f04321f966b4231371b21475bc4da, which is the second due to previous rebase:</p>
  
  <pre><code>commit 60b413512e616997c8b929012cf9ca56bf5c9113
  Author: Luca G. Soave &lt;luca.soave@gmail.com&gt;
  Date:   Tue Apr 12 23:50:15 2011 +0200
  
      add generic config/initializers/omniauth.example.rb
  
  commit af5c7bf16e6f04321f966b4231371b21475bc4da
  Author: Luca G. Soave &lt;luca.soave@gmail.com&gt;
  Date:   Fri Apr 22 00:15:50 2011 +0200
  
      show github user info if logged
  
  commit e6523efada4d75084e81971c4dc2aec621d45530
  Author: Luca G. Soave &lt;luca.soave@gmail.com&gt;
  Date:   Fri Apr 22 17:20:48 2011 +0200
  
      add multiple .container at blueprint layout
  
  commit 414ceffc40ea4ac36ca68e6dd0a9ee97e73dee22
  Author: Luca G. Soave &lt;luca.soave@gmail.com&gt;
  Date:   Thu Apr 21 19:55:57 2011 +0200
  
      add %h1 Fantastic Logo + .right for 'Sign in with Github'
  </code></pre>
  
  <p>I need to mantain </p>
  
  <ul>
  <li>the First commit 60b413512e616997c8b929012cf9ca56bf5c9113,</li>
  <li>the Third commit e6523efada4d75084e81971c4dc2aec621d45530 and </li>
  <li>the Last commit 414ceffc40ea4ac36ca68e6dd0a9ee97e73dee22 </li>
  </ul>
  
  <p>"throwing away" just the Second commit <strong>af5c7bf16e6f04321f966b4231371b21475bc4da</strong></p>
  
  <p>How can I do that?
  Thanks in advance 
  Luca</p>