public IActionResult Create(BeaconViewModel vm)
        {
            if (ModelState.IsValid)
            {
                var newBeacon = Mapper.Map<Beacon>(vm);

                // save to database
                _repository.AddBeacon(newBeacon);
            }
            return RedirectToAction("Index");
        }
        public IActionResult Edit(BeaconViewModel vm)
        {
            if (ModelState.IsValid)
            {
                var beaconToUpdate = Mapper.Map<Beacon>(vm);

                // save to database
                _repository.Edit(beaconToUpdate);
            }
            return RedirectToAction("Index");
        }