title: Create product from a module in prestashop
body: <p>I guys i try to create a custom product from a module with this code :</p>
  
  <pre><code>$defaultLanguage = new Language((int)(Configuration::get('PS_LANG_DEFAULT')));  
  /* Add a new product */
  $object = new Product();
  $object-&gt;price = 22;
  $object-&gt;id_tax_rules_group = 0;
  $object-&gt;name = 'test';
  $object-&gt;id_manufacturer = 0;
  $object-&gt;id_supplier = 0;
  $object-&gt;quantity = 1;
  $object-&gt;minimal_quantity = 1;
  $object-&gt;additional_shipping_cost = 0; 
  $object-&gt;wholesale_price = 0;
  $object-&gt;ecotax = 0;
  $object-&gt;width = 0;
  $object-&gt;height = 0;
  $object-&gt;depth = 0;
  $object-&gt;weight = 0;
  $object-&gt;out_of_stock = 0;
  $object-&gt;active = 0;
  $object-&gt;id_category_default = 18;
  $object-&gt;category = 18;
  $object-&gt;available_for_order = 0;
  $object-&gt;show_price = 1;
  $object-&gt;on_sale = 0;
  $object-&gt;online_only = 1;
  $object-&gt;meta_keywords = 'test';
  if($object-&gt;save())
      $object-&gt;add();
  echo "produit ajouté";
  </code></pre>
  
  <p>The code works fine, the product was added to the database but wasn't display in the back office, someone have an idea to solve this problem ? </p>