Killing a Worker while Tasks are Running Leaves Tasks in the Running Queue

[alanb1501]

Repro Steps

1. Create job foo
2. Start a worker to process foo, and don't invoke the callback
3. Kill the Worker

Check that the foo job is still marked in the running queue.

We need a way to detect when we have zero workers, and check that the running queue has items in it. For each item left in the item queue, check the job manifest, and if it's not complete, recycle the job by putting it back into the pending queue.