title: REGEX - Find td with specific class, including nested tables
body: <p>I've to parse over a piece of HTML. 
  It looks a bit like:</p>
  
  <pre><code>&lt;table&gt;
     &lt;tr&gt;
       &lt;td class="blabla"&gt; &lt;table&gt;&lt;tr&gt;&lt;td&gt;&lt;table&gt;&lt;tr&gt;&lt;td&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
       &lt;/td&gt;
     &lt;/tr&gt;
    &lt;tr&gt;
       &lt;td class="blabla"&gt; &lt;table&gt;&lt;tr&gt;&lt;td&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
       &lt;/td&gt;
     &lt;/tr&gt;
  &lt;/table&gt;
  </code></pre>
  
  <p>I need to extract each <code>td</code> with class <code>blabla</code>, but each of these cells could have 0 or more nested tables with many nested td's. I want to get </p>
  
  <pre><code>&lt;td class="blabla"&gt; ... many nested stuff ... &lt;/td&gt;
  </code></pre>
  
  <p>Thanks</p>