public void Test_Complete_CompletesTaskWhenDone()
{
//Arrange
string testDescription = "Mow the lawn";
DateTime? taskDate = new DateTime(2016, 7, 12);
Task testTask = new Task(testDescription, taskDate);
testTask.Save();
//Act
testTask.Complete();
bool result = testTask.IsDone();
//Assert
Assert.Equal(true, result);
}