hammerwork 2.0.1

Fixed

• In-memory result storage works. A job configured with ResultStorage::Memory had
  its result silently discarded: workers only stored ResultStorage::Database results.
  Workers now store them in an in-memory store owned by the JobQueue and shared by its
  clones, before the job is marked Completed, and get_job_result, delete_job_result,
  cleanup_expired_results and delete_job use it. Results expire at their TTL (checked
  on read and pruned as results are stored), and the store holds at most 10,000 results
  by default (queue::DEFAULT_MEMORY_RESULT_CAPACITY), evicting the one that expires
  soonest, or the oldest; set the limit with the new
  JobQueue::with_memory_result_capacity. In-memory results are per process: other
  processes, including cargo hammerwork and the web dashboard, don't see them, and
  they are lost on restart. See Job Results.
  TestQueue::delete_job now also deletes the job's result.