/**
  * Get a list of every event in Joind.in that doesn't exist in our system
  *
  * @return array
  */
 protected function listUnsyncedEvents()
 {
     $return = [];
     $conferences = $this->client->getEvents();
     $alreadyConferences = \Conference::all();
     $joindinIds = $alreadyConferences->map(function ($conference) {
         return (int) $conference->joindin_id;
     });
     $joindinIdsArray = $joindinIds->toArray();
     // @todo this should be a lot simpler if we can get the Collection working
     foreach ($conferences as $conference) {
         if (!in_array($conference['id'], $joindinIdsArray)) {
             $return[] = $conference;
         }
     }
     return $return;
 }