public void Test_Get_Returns_Car_with_given_Id()
        {
            var controller = new VehicleController();
            var actual = controller.Get("CC2D2644-DB27-477C-99AD-A34E6FD3F139");
            Assert.AreEqual("Silver", actual.Colour);
            Assert.AreEqual("Audi", actual.Make);
            Assert.AreEqual("A4", actual.Model);
            Assert.AreEqual("MEOWDI", actual.Registration);
            Assert.AreEqual("1996", actual.Year);


        }
 public void Test_Get_Returns_n_Cars()
 {
     var controller = new VehicleController();
     var actual = controller.Get();
     Assert.AreEqual(5, actual.Count());
 }