When possible, wake a background worker after committing a transaction that queues a job.
Make it possible to wake a worker to check for work with Que.wake!.
Setting a worker_count should set the mode appropriately.
Fix up interaction between Que.worker_count= and Que.mode=, and thoroughly spec logging thereof.
Fix a rare spec failure on Rubinius and probably JRuby.
Fix a nondeterministic spec failure on JRuby.
Tweaks to the most recent changelog entries.