INT-3316 BeanFactoryTypeConverter Concurrency

JIRA: https://jira.spring.io/browse/INT-3316

The `SimpleTypeConverter` delegate uses property editors
which are not thread safe. We protect against concurrent
access when the source is not a String, but when a String,
we delegate to the `STC`.

Synchronize access to the `STC.convertIfNecessary()` method.
INT-3288 Use Unique Queues for Tests

JIRA: https://jira.spring.io/browse/INT-3288

Possible crosstalk between in inbound and outbound channel
adapter tests - they used the same queue (foo). The outbound
test leaves a message in the queue.
INT-3041 Add Namespace Support For Retry Advice

JIRA: https://jira.spring.io/browse/INT-3041

Add namespace support to simplify configuration of
a `RequestHandlerRetryAdvice.

INT-3041 Polishing; PR Comments

* Allow a retry-advice element within the request-handler-advice-chain
* Clean up schema (should not have allowed `synchronization-factory` on
    the request-handler-advice-chain.

INT-3041 Polishing; PR Comment
INT-3319 Fix BeanFactory Propagation

JIRA: https://jira.spring.io/browse/INT-3319

The `MessageBuilderFactory` abstraction relies on the bean factory
being propagated to all classes that create messages.

Some classes were missed in the initial PR.