INT-3520: Add Reactor's `PersistentQueue` support

JIRA: https://jira.spring.io/browse/INT-3520
Well, I got your point.
`BlockingQueue.take()` ralies on `notEmpty.await()` `Condition`. That's why it doesn't "eat" CPU.
So, here we can just ignore `timeout` or use some simple `Thread.sleep(1)` or try to find more better solution with some low-API `Waiter`.
Thoughts?