title: jQuery - Make a table with fixed header sortable
body: <p>I have an HTML table on <a href="http://codepen.io/jgx/pen/wiIGc" rel="nofollow">this site</a></p>
  
  <p>The header of the table is fixed with JavaScript. Now I also want the possibility to sort each column. Therefore I used jQuery's <a href="http://tablesorter.com/docs/" rel="nofollow">tablesorter</a> plugin. The problem is that the JavaScript on codepen.io copys the header of the table. In the DOM there are now two table headers. <code>TableSorter</code> accesses the first table, which was copied, but this table has no <code>tbody</code> so the table won't be sorted by <code>TableSorter</code>.</p>
  
  <p>Is there a posibility to have both (table header fixed and sorting by clicking on columns)?</p>