/**
  * Adds new subscriber to the mailchimp list
  *
  * Works only if the license is new (checks for the empty id)
  *
  * @param License $license
  */
 public function addToList(License $license)
 {
     if (!$this->enabled) {
         return;
     }
     foreach ($this->lists as $list) {
         if ($license->isNew() && $license->getAddonKey() == $list['addon_key']) {
             $this->add($list['list_id'], $license);
         }
     }
 }