public void TestGetAllUsers()
        {
            Repos<User> repos = new Repos<User>();
            List<User> us = new List<User>();

            for (int i = 0; i < 5; i++)
            {
                us.Add(new User(i, "Name" + i));
                repos.Save(new User(i, "Name" + i));
            }

            foreach (User u in repos.GetAll())
            {
                Console.WriteLine(u);
            }

            var n = 0;
            foreach (User s in repos.GetAll())
            {
                Assert.AreEqual(us[n].Id, s.Id);
                Assert.AreEqual(us[n].Username, s.Username);
                n++;
            }
        }