title: Override prestashop admin TPL
body: <p>i'am trying to override Cart Rule by adding a new field (number of codes).
  I created a new class CartRule in /override/classes and I have added this line to definition array</p>
  
  <pre><code>'nb_codes' =&gt;    array('type' =&gt; self::TYPE_INT, 'validate' =&gt; 'isInt'),
  </code></pre>
  
  <p>and that work fine.
  I have one issue that i cannot visualize this field in the informations.tpl even if i override this view in /override/controllers/admin/templates/cart_rules</p>