public function store(Request $request)
 {
     $rules = ['name' => 'required|unique:school_years|min:4|max:255', 'start' => 'required|date', 'end' => 'required|date', 'course_handbook_id' => 'required|exists:course_handbooks,id'];
     $messages = ['name.required' => 'Por favor indique un nombre para el año lectivo.', 'name.min' => 'Ingrese un nombre adecuado.', 'start.required' => 'Es necesario definir la fecha de inicio.', 'end.required' => 'Es necesario definir la fecha de fin.'];
     $v = Validator::make($request->all(), $rules, $messages);
     if ($v->fails()) {
         return back()->withErrors($v)->withInput();
     }
     if ($request->get('start') > $request->get('end')) {
         return back()->withErrors(['range' => 'Las fechas son inconsistentes.'])->withInput();
     }
     SchoolYear::create($request->all());
     return back()->with('success', 'Año lectivo registrado exitosamente.');
 }
 /**
  * Run the database seeds.
  *
  * @return void
  */
 public function run()
 {
     $carbon = Carbon::now('America/Lima');
     $year = $carbon->year;
     $start = clone $carbon;
     $start->firstOfYear();
     $end = clone $carbon;
     $end->lastOfYear();
     $prev_start = clone $start;
     $prev_start->subYear();
     $prev_end = clone $end;
     $prev_end->subYear();
     // A past school year
     SchoolYear::create(['name' => 'Año ' . ($year - 1), 'start' => $prev_start, 'end' => $prev_end, 'course_handbook_id' => 1]);
     // Current school year
     SchoolYear::create(['name' => 'Año ' . $year, 'start' => $start, 'end' => $end, 'course_handbook_id' => 1]);
 }