JIRA: https://jira.spring.io/browse/INT-2595
* Add `group-timeout` and `group-timeout-expression` to the Correlation Endpoint
* Add logic to the `AbstractCorrelatingMessageHandler` to schedule group for `forceComplete`,
when the target `ReleaseStrategy` returns `false`
INT-2595: Polishing according PR comments
INT-2595: Expose `lock-registry` and further docs
INT-2595 Doc and Test Polishing
INT-2595: Fix typos
INT-2595 More Minor Doc Polish
eb0d1ddc84