private static void AddUser(TravelPlannerDbContext context, string userName, string password, string roleId)
        {
            var user = new ApplicationUser
            {
                UserName = userName,
                // IdentityManager requires an e-mail, even if we don't use it
                Email         = userName + "@test.com",
                SecurityStamp = Guid.NewGuid().ToString()
            };

            user.Roles.Add(new IdentityUserRole {
                RoleId = roleId, UserId = user.Id
            });

            user.PasswordHash = new PasswordHasher().HashPassword(password);
            context.Users.Add(user);
            try
            {
                context.SaveChanges();
            }
            catch (DbEntityValidationException ex)
            {
                throw;
            }
        }
        public static void DoSeed(TravelPlannerDbContext context)
        {
            var userRole        = context.Roles.Add(new IdentityRole("User"));
            var userManagerRole = context.Roles.Add(new IdentityRole("UserManager"));
            var adminRole       = context.Roles.Add(new IdentityRole("Admin"));

            AddUser(context, "TestUser1", "test", userRole.Id);
            AddUser(context, "TestUserManager1", "test", userManagerRole.Id);
            AddUser(context, "TestAdmin1", "test", adminRole.Id);
        }