public function deleteHistorie()
 {
     $this->historie = new Historie($this->request->id);
     if ($this->historie->delete()) {
         FlashMessage::success(Strings::GELOESCHT);
     } else {
         FlashMessage::danger(Strings::NICHT_GELOESCHT);
     }
 }
 public static function wertAenderung(BaseEntity $entity, $feld, $alterWert, $neuerWert)
 {
     $historie = new Historie();
     $historie->hi_benutzer = Security::getUserId();
     $historie->hi_beschreibung = '';
     $historie->hi_feld = substr($feld, 0, 20);
     // TODO
     $historie->hi_alter_wert = $alterWert;
     $historie->hi_neuer_wert = $neuerWert;
     $historie->hi_timestamp = new \DateTime();
     $historie->hi_entity = $entity->getEntityName();
     $historie->hi_entity_id = $entity->id;
     $historie->save();
     unset($historie);
 }