title: How to use Cleaner, lxml.html without returning div tag?
body: <p>I have this code:</p>
  
  <pre><code>evil = "&lt;script&gt;malignus script&lt;/script&gt;&lt;b&gt;bold text&lt;/b&gt;&lt;i&gt;italic text&lt;/i&gt;"
  cleaner = Cleaner(remove_unknown_tags=False, allow_tags=['p', 'br', 'b'],
                    page_structure=True)
  print cleaner.clean_html(evil)
  </code></pre>
  
  <p>I expected to get this:</p>
  
  <pre><code>&lt;b&gt;bold text&lt;/b&gt;italic text
  </code></pre>
  
  <p>But instead I'm getting this:</p>
  
  <pre><code>&lt;div&gt;&lt;b&gt;bold text&lt;/b&gt;italic text&lt;/div&gt;
  </code></pre>
  
  <p>Is there an attribute to remove the <code>div</code> tag wrapper?</p>