title: How to show Git log history (i.e., all the related commits) for a sub directory of a Git repository
body: <p>Let’s say that I have a Git repository that looks like this:</p>
  <pre><code>foo/
    .git/
    A/
     ... big tree here
    B/
     ... big tree here
  </code></pre>
  <p>Is there a way to ask <code>git log</code> to show only the log messages for a specific directory? For example, I want to see what commits touched files in <em>foo/A</em> only.</p>