Fix while Block Formatting in SimplePool
INT-2994 Advice Chain Config via Annotations

Allow configuration of request handler advice chain using

- ServiceActivator
- Filter
- Splitter
- Transformer

annotations.

Also, with splitter, allow setting discardWithinAdvice (See
INT-2938).

INT-2994 Polishing: PR Comments

- Change adviceChain attribute to an array
- Use a boolean for the discardWithinAdvice attribute

INT-2994 Handler Advice Doc Polishing

Add a paragraph about Advice Order.
INT-3051 Derive Script Language from Extension

Make 'lang' attribute optional on a script element and
attempt to derive the language from the file extension.

Change return value on ScriptParser.deriveLanguageFromExtension to the language name

Polishing (PR Comments)
INT-2243: Delayer: Add 'expression' Support

Previously, the `<delayer>` provided a `delay-header-name` attribute.
In complex cases there was need to precede it with `<header-enricher>`.

* Add support for an 'expression' attribute and sub-element
* Deprecate `delay-header-name`
* Make `DelayHandler.DelayedMessageWrapper` *public* to allow access for Messages in the Store
* Add tests
* Add 'What's new' section
* Polishing Delayer's doc regarding new abilities

JIRA: https://jira.springsource.org/browse/INT-2243, https://jira.springsource.org/browse/INT-3049

INT-2243: ban delay-header-name with expression

INT-2243 Polishing

INT-2243: fall-back to default on Eval Exception

INT-2243: DelayedMessageWrapper refactoring

* Make `DelayedMessageWrapper` Spring Data Mongo mapping compatible.
In terms of Spring Data - add Persistence Constructor

INT-2243 add 'ignore-expression-failures' support

* Add `ignore-expression-failures` to the `<delayer>`
* Add tests for `ignore-expression-failures`
* Add a note to the RM
* Describe SpEL side-effects for `DelayHandler`

Doc Polishing
INT-3078, INT-3079: Redis & Gemfire Delayer Tests

Add Redis & Gemfire Delayer integration tests
to be sure that Delayer works correctly

JIRA: https://jira.springsource.org/browse/INT-3078
https://jira.springsource.org/browse/INT-3079
INT-3112 Fix OOM in SimplePool

The SimplePool maintains an 'allocated' set, for the sole reason
of preventing a "foreign" (non-managed) object being returned.

When a pool item is detected as stale, it is removed from the pool
but remains in the 'allocated' set.

Add a test to verify the allocated size is reduced when a stale
item is popped from the pool.

Add a FileTransferringMessageHandler test (where the problem was
discovered).

Fix a test in TCP to expect a close().

Polishing

Do not allow returning null items to just release a permit - it
cannot remove the item from allocated. Clients must return the
stale item to the pool so it can be refreshed on the next get.

Only used by the TCP caching CF when returning a connection when
the factory is not running; but should not be allowed.

Also, protect against double release - not currently an issue with
existing users of SimplePool, but should be protected against. Could
cause the permit count to exceed the pool size.

Add inUse Set to the pool so we can detect attempts to release an
item that has already been released.