/**
  * return sorted collaborator list
  *
  * @param SortRequest $request
  * @param Collaborator $collaborator
  * @return \Illuminate\Contracts\View\Factory|\Illuminate\View\View
  */
 public function sort(SortRequest $request, Collaborator $collaborator)
 {
     $model = $collaborator->sort($request->get('column'), $request->get('type'))->get();
     return view('collaborator.blocks.filter', ['model' => $model]);
 }