public void Tasks_Cleanup()
{
var id = Guid.NewGuid();
var mre = new ManualResetEvent(false);
TasksHost.Enqueue <MyTask>(id,
completed: (dic) =>
{
mre.Set();
});
mre.WaitOne();
TasksHost.Cleanup();
var result = TasksHost.GetHistory(id);
Check.That(result).IsNull();
}