/**
  * Add one asset to the asset collection
  *
  * @param Asset $asset
  * @return boolean
  */
 public function addAsset(Asset $asset)
 {
     if ($this->assets->contains($asset) === FALSE) {
         $this->assets->add($asset);
         return TRUE;
     }
     return FALSE;
 }
 /**
  * Add one asset to the asset collection
  *
  * @param Asset $asset
  * @return boolean
  */
 public function addAsset(Asset $asset)
 {
     if ($this->assets->contains($asset) === false) {
         $this->assets->add($asset);
         return true;
     }
     return false;
 }