public async void CancelDownloads(CancelDownloads cancel)
        {
            Console.WriteLine("[Downloadanager] CancelDownloads");

            var queued = _repo.ByState(new [] {
                State.Downloading,
                State.Waiting,
                State.Error
            });

            foreach (var queue in queued)
            {
                queue.Cancel();
            }

            _repo.UpdateAll(queued);

            foreach (var queue in queued)
            {
                await _bus.SendAsync <NotifyProgress> (new NotifyProgress {
                    Url      = queue.Url,
                    Download = queue
                });
            }
        }