* INT-4542: CorrMH: Use popSequenceDetails properly
JIRA: https://jira.spring.io/browse/INT-4542
Perform a `MessageBuilder.popSequenceDetails()` for those
`MessageGroupProcessor` results which are not `Message`
or `Collection<Message>`
**Cherry-pick to 5.0.x**
* * Add `AbstractCorrelatingMessageHandler.popSequenceDetails` property
* * Rename property to just a `popSequence`
* * Fix JavaDocs on the `AbstractCorrelatingMessageHandler.setPopSequence()`
* Fix Docs typos and language
* finish the `RouterTests.testNestedScatterGather()`
0f5cfd4314