public async Task<UserViewModel> GetUserByNameAsync(string name)
        {
            var user = await _users.GetUserByNameAsync(name);

            if (user == null)
            {
                return null;
            }

            var viewModel = new UserViewModel
            {
                UserName = user.UserName,
                Email = user.Email,
                DisplayName = user.DisplayName
            };

            var userRoles = await _users.GetRolesForUserAsync(user);

            viewModel.SelectedRole = userRoles.Count() > 1 ?
                userRoles.FirstOrDefault() : userRoles.SingleOrDefault();

            viewModel.LoadUserRoles(await _roles.GetAllRolesAsync());

            return viewModel;
        }
        public async Task<ActionResult> Create()
        {
            var model = new UserViewModel();
            model.LoadUserRoles(await _roleRepository.GetAllRolesAsync());

            return View(model);
        }