title: Include submodule commit messages with "git log"
body: <p>Suppose I have two versions in my repository... each has been tagged as follows:</p>
  
  <ul>
  <li>Tag1</li>
  <li>Tag2</li>
  </ul>
  
  <p>Now suppose that a commit updated a submodule reference to point to a new submodule commit between Tag1 and Tag2.  I run the following command, and get this:</p>
  
  <pre><code># show commits between these two tags
  git log Tag1..Tag2
  
  
  commit be3d0357b93322f472e8f03285cb3e1e0592eabd
  Author: James Johnston &lt;snip&gt;
  Date:   Wed Jan 25 19:42:56 2012 +0000
  
      Updated submodule references.
  </code></pre>
  
  <p>In this case, the only change was an update of the submodule.  How do I get the submodule commits to be interleaved with the parent repository commits?</p>
  
  <p>Specifically, in this example, suppose that the parent repository points to the SubTag5 tag in the submodule.  Two commits later in the submodule is a SubTag6 tag.  The commit shown updated the submodule pointer to point to SubTag6 instead of SubTag5.  What I would like to do is have <code>git log</code>, in addition to the commit it already printed, print the two submodule commits as well that brought the submodule from SubTag5 to SubTag6.</p>