public function postForm(CampagneRequest $request)
 {
     $Campagne = new Campagne();
     $Campagne->nom_campagne = $request->input('nom_campagne');
     $Campagne->description_campagne = $request->input('description_campagne');
     $Campagne->date_debut = $request->input('date_debut');
     $Campagne->date_fin = $request->input('date_fin');
     $Campagne->date_fin_vote = Carbon::parse($request->input('date_fin'))->addWeek(self::nbSemainesVote);
     $Campagne->choix_binaire = $request->input('choix_binaire') == null ? false : true;
     $Campagne->choix_validation = $request->input('choix_validation') == null ? false : true;
     $Campagne->save();
     return Redirect::to('admin');
 }