public function store(PracticanteRequest $request)
 {
     $practicante = new Practicante($request->all());
     if ($practicante->policecourse) {
         $practicante->policecourse = implode(',', $practicante->policecourse);
     }
     $practicante->save();
     Flash::success('Se ha agregado el practicante ' . $practicante->name);
     return redirect()->route('admin.practicantes.index');
 }