/**
  * Responds to requests to GET /routines/edit/{id}
  */
 public function getEdit($id)
 {
     $routine = Routine::with('exercises')->find($id);
     if (!$this->isAdminOrCreator($routine)) {
         return response('Unauthorized.', 401);
     }
     $options = Routine::getOptions(['goals', 'frequencies', 'difficulties']);
     return view('routines.edit', ['routine' => $routine, 'options' => $options]);
 }