Issue: SPR-13446

Issue: SPR-13447

Issue: SPR-13328

Issue: SPR-13443

Issue: SPR-13213

Latest dependency updates (Hibernate ORM 5.0.1, JasperReports 6.1.1, Joda-Time 2.8.2, SnakeYAML 1.16)

Issue: SPR-13425

This change adds a new `getDateHeader` method that converts date header
Strings to long values - making tests more readable.

This feature is also documented in the "what's new section" for 4.2.

Prior to this commit, requests with an empty body and no Content-Type
header set would fail with a HttpMediaTypeNotSupportedException when
mapped to a Controller method argument annotated with
@RequestBody(required=false).
In those cases, the server implementation considers with an
"application/octet-stream" content type and polls messageconverters for
conversion. If no messageconverter is able to process this request, a
HttpMediaTypeNotSupportedException is thrown.

This change makes sure that such exceptions are not thrown if the
incoming request has:
* no body
* no content-type header

In this case, a null value is returned.

Issue: SPR-13147

Issue: SPR-12081

Issue: SPR-13421

Includes a revision for consistent and defensive Servlet 3.0 method calls across Spring's web abstraction (in particular, also working in debug mode where method references may get resolved early, so ternary expressions are to be avoided).

Issue: SPR-13420

Issue: SPR-13411

This commit improves the documentation in the reference manual for the
HtmlUnit & Selenium WebDriver integration in the Spring MVC Test
framework by mentioning the group and artifact IDs required for this
functionality.

Issue: SPR-13299

Issue: SPR-13405

Issue: SPR-13413

Issue: SPR-13409

Properties values get properly converted to generic Map types (fixing 4.x regression without use of ConversionService)

Issue: SPR-13256

* SPR-13405:
  Support transitive implicit attribute aliases with @AliasFor

This commit picks up where 3eacb837
(SPR-13345) left off by adding support for transitive implicit aliases
configured via @AliasFor.

Issue: SPR-13405

This commit removes unnecessary not-null checks for annotation
attribute alias names.