change html mapping to use 'Drupal' set of html tags if possible

<h1> <h2> <h3> <h4> <a> <em> <strong> <cite> <span> <div> <blockquote>
<code> <ul> <ol> <li> <dl> <dt> <dd> <p> <table> <td> <tr> <br> <img>
<pre> <sup> <hr> <!-- -->