/**
  * Deletes the file bound to this controller
  * 	
  * @param  SS_HTTPRequest $r
  * @return SS_HTTPResponse
  */
 public function handleDelete(SS_HTTPRequest $r)
 {
     if (!$this->file->canDelete()) {
         return $this->httpError(403);
     }
     $this->file->delete();
     return new SS_HTTPResponse('OK');
 }