- Added BodyInserter for MultiValueMap form data in BodyInserters
 - Added BodyExtractor to MultiValueMap in BodyExtractors

Issue: SPR-15144

Issue: SPR-14880

Issue: SPR-14492

Issue: SPR-14503

Issue: SPR-15068

Issue: SPR-15065

This commit ensures that verifying a request, which includes finding
and updating expectations, is done synchronously to avoid concurrent
modification exceptions.

Technically SimpleRequestExpectationManager is not even expected to see
concurrent requests by definition but with
UnorderedRequestExpectationManager it can happen.

Issue: SPR-15029

Issue: SPR-15096
(cherry picked from commit 801b93a0)

Issue: SPR-14829

Issue: SPR-15145

In addition to the updates from PR#1297 this commit adds an integration
test and fixes for the resulting failures with RxNetty, Reactor Netty,
and Undertow.

Also replaced use of URLDecoder which is not for decoding URIs with use
of UriUtils for decoding query parameters.

Issue: SPR-15140

%-encoded strings were injected undecoded into @RequestParam variables,
which does not coincide with spring-webmvc behaviour. This commit
fixes AbstractServerHttpRequest.getQueryParams() to correctly return
decoded name-value pairs.

Issue: SPR-15140

This commit adds a DataBuffer Encoder and Decoder, and uses it in
the annotation-based processing model.

Note that these codecs are not used in the functional processing model,
since the BodyInserter/BodyExtractor already have methods for
writing/reading DataBuffers.

Issue: SPR-15148

Ensure there is no "?" at the end of the generated URI when there is
no query available.

This modification fixes the way AbstractView retrieves the
RequestDataValueProcessor bean, correctly returning null if there
is no bean of such type at the Application Context.

This avoids an exception in RedirectView (which extends AbstractView)
when trying to post-process the URL generated for redirection, when
no RequestDataValueProcessor exists.

Issue: SPR-15136

Issue: SPR-15154

Issue: SPR-15155

Issue: SPR-15153

Issue: SPR-15154

Issue: SPR-11890

Issue: SPR-11890

This commit changes the `Bootstrap` to create a SSL Handler with
advisory peer information; this enables support for SNI.

Issue: SPR-15101

Issue: SPR-15151

Issue: SPR-14880

StandardMultipartHttpServletRequest identifies MaxUploadSizeExceededException through keywords in message

Issue: SPR-9294

Issue: SPR-15139

Introduces dedicated MethodArgumentResolutionException for spring-messaging invocations.

Issue: SPR-15139

Issue: SPR-15146

Issue: SPR-15145

Issue: SPR-15125

Issue: SPR-15116

(plus Jackson 2.8.6, Netty 4.1.7, JRuby 9.1.7)

Issue: SPR-14998