Change uses of Job.queue to Job.enqueue.
Merge branch 'master' into 0.6-docs
Update docs for priority and run_at variable renamings.
Fix a strangely worded changelog entry.
Add docs on multiple queues.
Merge branch 'master' into 0.6-docs
Document Que.enqueue.
Add a doc on schema migrations.
Merge branch 'master' into 0.6-docs

Conflicts:
	CHANGELOG.md
Add changelog entry on migrating the schema when upgrading.
Fix changelog typo.
Add Que::Job.run, to invoke job logic without involving the queue. Closes #26.
Merge branch 'master' into 0.6-docs

Conflicts:
	CHANGELOG.md
Minor documentation tweaks.
Add docs on shutting down safely and using timeouts in jobs.
Add documentation on running with Puma (and presumably Unicorn).
Bump version to 0.6.0.
Deprecate JobClass.queue, and the default_priority and default_run_at instance variables.
Avoid an errant deprecation warning.
Note deprecations in the CHANGELOG.