Polishing
Groovy-based bean definitions

Formerly known as the Grails BeanBuilder, now in Spring proper. Based on https://github.com/spring-projects/spring-framework/pull/355 but heavily refactored and restructured.

Issue: SPR-7123
Upgraded to JCache 0.11 for Spring Framework 4.0 RC1

Unfortunately, the JCache API changed quite a bit since 0.6. We're building against a snapshot of JCache 0.11 now, tracking its way to final after the Public Review Ballot.
Polish GroovyBeanDefinitionReader formatting

Consistent use of tabs and remove trailing whitespace.

Issue: SPR-7123
Polish ResolvableType & SerializableTypeWrapper

Fix 'missing serialVersionUID' warnings, support for void.class types
and refine resolve() algorithm to support narrowed types.

Issue: SPR-10973
Support for MultiValueMap in MapToMapConverter

Refactor TypeDescriptor to use ResolvableType in order to retain full
generic type information, in the process fixing MultiValueMap support
in MapToMapConverter.

Issue: SPR-9499
Upgrade to reactor 1.0 RC1 and remove MessageChannel

This change upgrades reactor to 1.0 RC1 and also removes the
reactor-based message channel in favor of the one available from
org.projectreactor:reactor-spring.
Fix issue with forwarding messaging to STOMP broker
Refactor STOMP relay session

This change consolidates TCP-related logic in the StompRelaySession. As
a result the sub-class SystemStompRelaySession now contains only logic
intrinsic to the shared system session.
Add TCP abstractions to spring-messaging

This change adds abstractions for opening and managing TCP connections
primarily for use with the STOMP broker support. As one immediate
benefit the change makes the  StompBrokerRelayMessageHandler more
easy to test.
Fix issue in AbstractMessagingTemplate