Prior to this commit, information regarding avoiding false positives
when testing with JPA had already been added to the Testing chapter of
the reference manual. However, the example did not work properly and
the accompanying text mixed concepts from Hibernate and JPA.

This commit fixes the @Autowired/@PersistenceContext bug, updates the
text, and marks each test as @Transactional in order to avoid any
misinterpretation.

Issue: SPR-9032

Prior to this commit, @BeforeTransaction and @AfterTransaction could
only be declared on methods within test classes. However, JUnit 5 as
well as some existing third-party Runner implementations for JUnit 4
already support Java 8 based interface default methods in various
scenarios -- for example, @test, @BeforeEach, etc.

This commit brings the Spring TestContext Framework up to date by
supporting the declaration of @BeforeTransaction and @AfterTransaction
on interface default methods.

Issue: SPR-14183

This commit updates the Testing chapter in the reference manual to
refer explicitly to JUnit 4 instead of just "JUnit" (where appropriate)
in order to avoid confusion with forthcoming support for JUnit 5.

SendTo and SendToUser are treated as mutually exclusive. The addition of
type-level support in 4.3. RC1 however did not consider the possibility
to mix and match of the two betwee type and method level.

This commit consolidates the detection of SendTo and SendToUser
annotations and considers them all together.

Issue: SPR-14238

Issue: SPR-14240

Prior to this commit, setting the `forceEncoding` option would force
encoding on both requests and responses.

This commit adds two new setters and a new constructor to differentiate
both options: forcing the encoding on the request and/or on the
response.

You can now define this filter programmatically using those options or
update your servlet XML configuration like:

```
<filter>
  <filter-name>characterEncodingFilter</filter-name>
  <filter-class>o.sf.web.filter.CharacterEncodingFilter</filter-class>
  <init-param>
     <param-name>encoding</param-name>
     <param-value>UTF-8</param-value>
  </init-param>
  <init-param>
    <param-name>forceRequestEncoding</param-name>
    <param-value>true</param-value>
  </init-param>
  <init-param>
    <param-name>forceResponseEncoding</param-name>
    <param-value>false</param-value>
  </init-param>
</filter>

```

Issue: SPR-14240

Issue: SPR-14239

Prior to this commit, the `ResourceHttpMessageConverter` would support
all HTTP Range requests and `MethodProcessors` would "wrap" controller
handler return values with a `HttpRangeResource` to support that use
case in Controllers.

This commit refactors that support in several ways:
* a new ResourceRegion class has been introduced
* a new, separate, ResourceRegionHttpMessageConverter handles the HTTP
range use cases when serving static resources with the
ResourceHttpRequestHandler
* the support of HTTP range requests on Controller handlers has been
removed until a better solution is found

Issue: SPR-14221, SPR-13834

Issue: SPR-14234

The underlying issue has been fixed in e45d33f9 and this commit is merely
adding a test of the expected behaviour.

Issue: SPR-14233

Issue: SPR-14233

Issue: SPR-14233

This commit makes sure that HTTP request headers containing ETag values
are properly parsed and not simply tokenized using a "," separator.
Indeed, ETags can legally contain separator characters such as " " and
",".

Issue: SPR-14216

Issue: SPR-14230

Issue: SPR-14229

Includes renaming of internal delegate to CacheOperationExpressionEvaluator.

Issue: SPR-14230

Issue: SPR-14231

This commit allows to configure a custom WebJarAssetLocator in
WebJarResourceResolvers.

Issue: SPR-14092

Prior to this change, getting header values with `HttpHeaders` when
headers are multi-valued would cause issues.
For example, for a given HTTP message with headers:
    Cache-Control: public, s-maxage=50
    Cache-Control: max-age=42

Getting a `List` of all values would return <"public", "s-maxage=50">
and getting the header value would return "public, s-maxage=50".

This commit takes now into account multi-valued HTTP headers and adds
new getters/setters for "If-Match" and "If-Unmodified-Since" headers.

Note that for ETag-related headers such as "If-Match" and
"If-None-Match", a special parser has been implemented since ETag values
can contain separator characters.

Issue: SPR-14223, SPR-14228

Resources are now retrieved using the application context in order to
support natively non-classpath locations like /WEB-INF/...

As a consequence of this refactoring, ScriptTemplateView#createClassLoader()
protected method as been removed, since it did not make sense anymore with
this new resource loading implementation.

Issue: SPR-14210

Issue: SPR-14201

* pr/1046:
  "final" for public static fields in ReflectionUtils

Closes gh-1046

Issue: SPR-14214

Issue: SPR-14200

Issue: SPR-14195

CachedIntrospectionResults explicitly introspects implemented interfaces (for Java 8 default methods)

Issue: SPR-14198

Prior to this change, setting both "If-None-Match" and
"If-Unmodified-Since" conditional request headers would check for both
conditions to be met.

This commit fixes this behavior to follow the RFC7232 Section 6:
> entity tags are presumed to be more accurate than date validators

So in case both conditions are present, the "If-None-Match" condition
takes precedence.

Issue: SPR-14224

Issue: SPR-14190

Issue: SPR-14205