title: Mercurial: Creating a diff of two commits
body: <p>Is there a way to get the changes of two commits with mercurial?
  The second commit is not directly after the first one, there are some other ones between them.</p>
  
  <p>I tried</p>
  
  <pre><code>hg diff [some params] --change xxxxx --change yyyyy &gt; file.patch
  </code></pre>
  
  <p>but that only includes the last changeset.</p>
  
  <p>If there is no way to achieve this with hg, is there maybe a tool to combine patches?</p>