public function downvote($id)
 {
     \App::setLocale(Auth::user()->language());
     $user = Auth::user();
     $propositionFactory = new PropositionFactory();
     if (Carbon::now()->diffInDays(Carbon::createFromTimestamp(strtotime($propositionFactory->getProposition($id)->deadline())), false) <= 0) {
         abort(403, trans('messages.unauthorized'));
     }
     if ($propositionFactory->getUserVoteStatus($id, $user->userId()) == false) {
         $propositionFactory->downvote($id, $user->userId(), $user->googleEmail());
         return redirect()->route('proposition', $id);
     } else {
         abort(403, trans('messages.unauthorized'));
     }
 }