Robust Redis dequeue implemented & tested

commit e750b30c42050c227ac2c453bbb13f4656c5a7c6
Author: Michael Marconi <michael@modeltwozero.com>
Date:   Tue Feb 5 22:34:42 2013 +0000

    Robust Redis dequeue implemented & tested

    I've had to disable the API tests in the suite, as they are flickering :-(

commit ff35481084d5d61fd1c27daf475881fe64b4799e
Author: Michael Marconi <michael@modeltwozero.com>
Date:   Tue Feb 5 11:25:05 2013 +0000

    Use an atomic pop/push

    BRPOPLPUSH ensures we can't lose the job in flight!