Description:
------------
I've been looking at the "alpha" or "beta" epub docs (depending what you call them). These are failing on my ereader, and after pushing the epub through a validator, there are a lot element errors. These are present on the HTML pages as well.

Basically these are all nested elements (div, ul, p) within a P tag (which you can't do). The code snippet below is from the "What is PHP page". Around half of the occurances are this simple and the enclosing p tag removed.

There are a lot of others where there are several instances of incorrect nesting in a paragraph, which need the closing p tag moving to the correct location.

Test script:
---------------
   <p class="para">
    <div class="example" id="example-1">
     <div class="info"><p><b>Example #1 An introductory example</b></p></div>
     <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
&lt;!DOCTYPE&nbsp;HTML&nbsp;PUBLIC&nbsp;"-//W3C//DTD&nbsp;HTML&nbsp;4.01&nbsp;Transitional//EN"<br />&nbsp;&nbsp;&nbsp;&nbsp;"http://www.w3.org/TR/html4/loose.dtd"&gt;<br />&lt;html&gt;<br />&nbsp;&nbsp;&nbsp;&nbsp;&lt;head&gt;<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;title&gt;Example&lt;/title&gt;<br />&nbsp;&nbsp;&nbsp;&nbsp;&lt;/head&gt;<br />&nbsp;&nbsp;&nbsp;&nbsp;&lt;body&gt;<br /><br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #0000BB">&lt;?php<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #007700">echo&nbsp;</span><span style="color: #DD0000">"Hi,&nbsp;I'm&nbsp;a&nbsp;PHP&nbsp;script!"</span><span style="color: #007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">?&gt;<br /></span><br />&nbsp;&nbsp;&nbsp;&nbsp;&lt;/body&gt;<br />&lt;/html&gt;</span>
</code></div>
     </div>

    </div>
   </p>