Small maintenance release that adds reschedule overloads for BackgroundJob and IBackgroundJobClient types and fixes tricky case with generics and inheritance when creating a background job.

Hangfire.Core

• Added – Add reschedule functionality to BackgroundJob and IBackgroundJobClient (by @chrischu).
• Fixed – ArgumentNullException with tricky generic type with inheritance case for jobs.
• Fixed – Display “Aborted servers will be removed…” note only once aborted threshold passed.