Includes OkHttp MockWebServer 3.12.1.

Includes JRuby 9.2.5 and Jetty Reactive HttpClient 1.0.2.

Includes JAX-WS 2.3.1, Awaitility 3.1.3, OkHttp 3.12, Woodstox 5.2.

Includes reordering of web dependency declarations.

Includes Hibernate ORM 5.1.16 and Hibernate Validator 6.0.13.

Includes Groovy 2.5.2, Undertow 2.0.12, Hibernate Validator 6.0.12.

Issue: SPR-17129

Issue: SPR-17124

Includes latest dependency updates (Mockito 2.21, Log4J 2.11.1, Hibernate ORM 5.3.4, Protobuf 3.6.1, JRuby 9.2, HtmlUnit 2.32, Selenium 3.14) for Spring Framework 5.1.

Issue: SPR-16388
Issue: SPR-16239

This commit introduces Protobuf support in WebFlux via dedicated
codecs.

Flux<Message> are serialized/deserialized using delimited Protobuf
messages with the size of each message specified before the message
itself. In that case, a "delimited=true" parameter is added to the
content type.

Mono<Message> are expected to use regular Protobuf message
format (without the size prepended before the message).

Related HttpMessageReader/Writer are automatically registered when the
"com.google.protobuf:protobuf-java" library is detected in the classpath,
and can be customized easily if needed via CodecConfigurer, for example
to specify protocol extensions via the ExtensionRegistry based
constructors.

Both "application/x-protobuf" and "application/octet-stream" mime types
are supported.

Issue: SPR-15776

Leverage https://github.com/jetty-project/jetty-reactive-httpclient
to add support for Jetty in WebClient via JettyClientHttpConnector.

Implemented with buffer copy instead of optimized buffer wrapping
because the latter hangs since Callback#succeeded doesn't allow
releasing the buffer and requesting more data at different times
(required for Mono<DataBuffer> for example).
See https://github.com/eclipse/jetty.project/issues/2429.

Issue: SPR-15092

Issue: SPR-17058

Prior to this commit, the generated POMs for Spring Framework modules
would contain unneeded/harmful information from the Spring Framework
build:

1. The BOM imports applied to each module by the dependency
management plugin, for example for Netty or Reactor Netty.
Spring should not export that opinion to its POMs.

2. The exclusion of "org.slf4:jcl-over-slf4j" from *all* dependencies,
which made the POMs much larger than necessary and suggested to
developers that they should exclude it as well when using all those
listed dependencies. In fact, only Apache Tiles currently brings that
transitively.

This commit removes that information from the POMs.
The dependencyManagement Gradle plugin is disabled for POM generation
and we manually resolve the dependency versions during the generation
phase.
The Gradle build is streamlined to exclude "org.slf4:jcl-over-slf4j"
only when necessary.

Issue: SPR-16893

...now that 0.8 is also listed in the Reactor bom.

Issue: SPR-16387

Issue: SPR-16387

Issue: SPR-16387

Issue: SPR-16470

Practically no changes to RxNetty for a year and efforts underway to
rebuild 0.6.x based on a current Reactor Netty base.

Aside from the extra time to run integration tests having two
Netty-based servers can also cause false alarms such as ByteBuf leaks
related to RxNetty.

Includes upgrade to Hibernate Validator 6.0.4 (where applicable)

Issue: SPR-16115

Upgrade to JAXB 2.3, JAX-WS 2.3, Annotations 1.3.1, Interceptor 1.2.1.
Also includes Log4J 2.9.1 and Asciidoctor 1.5.6.

Latest dependency updates (POI 3.17, Rome 1.8, EhCache 3.4, Caffeine 2.5.6, RxJava 2.1.4, Tomcat 8.5.21, JRuby 9.1.13, Rhino 1.7.7.2)

Includes latest dependency updates (Netty 4.1.15, Undertow 1.4.19)

Issue: SPR-15808

This reverts commit 3e2f6c84.

This commit applies the Dependency Management Plugin to modules that
require it; right now Spring Framework is importing BOMs for Netty and
Reactor dependencies only.

Instead of applying those BOMs to all modules, they're applied only
where they're needed.

Issue: SPR-15885

The main `build.gradle` file contains now only the common build
infrastructure; all module-specific build configurations have
been moved to their own build file.

Issue: SPR-15885