Moved worker pool test to YieldingWaitStrategy
A bit better padding in the SingleProducerSequencer.  Remove backOffCount counter
Added support for timeouts on consuming from the ring buffer
Small fix to Disruptor DSL for WorkPool shutdown
Remove capacity argument on RingBuffer.tryPublishEvent, it wasn't used
Update build number to beta4.
Interrupt threads before waiting for them to terminate to ensure they aren't still waiting on a lock.  Fixes intermittency in DisruptorTest.