Add annotation processor to `spring-boot-test` and
`spring-boot-test-autoconfigure`.

Fixes gh-6893

In 1.4.0 we used Elasticsearch 2.3.5 and Jackson 2.8. This
combination was incompatible in some circumstances due to a change
in Jackson (gh-6508). With Elasticsearch 2.4 yet to be released at the
time, the only way to restore compatibility was to downgrade Jackson.

With the release of Elasticsearch 2.4 we have another option: revert
the Jackson downgrade and upgrade Elasticsearch instead. While we
normally wouldn't consider upgrading to a new minor version of a
dependency in a maintenance release we have to do something to restore
compatibility. The alternative is to downgrade Jackson but that will
affect more people (Jackson is more widely used than Elasticsearch)
and will lose some functionality that was new in Jackson 2.8 that
people may already be relying upon.

This commit restores the use of Jackson 2.8 – including the
2.8-specific dependency management – and upgrades to Elasticsearch 2.4

Closes gh-6868

Closes gh-6827

Breaking API changes in Gradle 3.0 make it impossible to support
it reliably alongside Gradle 1 and 2 without mainintaining multiple
versions of our Gradle plugin. This commit updates the documentation
to note that Gradle 3 is not supported.

Closes gh-6880

Previously, in a war deployment, the web environment’s property sources
were initialized using the servlet context after the application’s
configuration had been read by ConfigFileApplicationListener. This
meant that spring.config.location configured via the servlet context
had no effect.

This commit adds a new ApplicationListener,
ServletContextApplicationListener, that initialises the configurable
web environment’s property sources using the servlet context. It’s
ordered with higher precedence than ConfigFileApplicationListener to
ensure that any properties defined in the servlet context are available
when loading the application’s configuration.

Closes gh-6801

Closes gh-6892

@WebAppConfiguration expects a mock web environment. If it is used
in conjuction with @SpringBootTest configured with a RANDOM_PORT or
DEFINED_PORT web environment a null pointer exception occurs as an
assumption that's made by MockServerContainerContextCustomizer doesn't
hold true in a non-mock web environment.

This commit updates SpringBootTestContextBootstrap to detect the
illegal configuration combination and fail fast, advising the user
to remove @WebAppConfiguration or reconfigure @SpringBootTest.

Closes gh-6795

Rename AutoConfigureReportTestExecutionListener to
SpringBootDependencyInjectionTestExecutionListener and ensure that it
replaces any existing DependencyInjectionTestExecutionListener.

Prior to this commit the registration of two DependencyInjection
listeners would cause @PostConstruct methods on tests to be called
twice.

In order to allow the standard DependencyInjectionTestExecutionListener
to be removed a new DefaultTestExecutionListenersPostProcessor interface
has been introduced.

Fixes gh-6874

Closes gh-6827

Update `ConfigFileApplicationListener` so that active profiles set in
properties files that overlap with `spring.profiles.default` can still
be set.

Prior to this commit if `spring.profiles.active` happened to specify
a profile name that was also in `spring.profiles.default` it would
not get applied.

Fixes gh-6833

Tomcat 8.5.5 has change the default value of `validationInterval` to
3000. See https://bz.apache.org/bugzilla/show_bug.cgi?id=59923 for
details.

See gh-6703
See gh-6657

See gh-6870

This reverts commit c54cdd67.

As part of the upgrade, Tomcat now requires a keystore to contain
an X.509 certificate. The two stores used in our tests have been
updated by exporting their private keys and adding them as
certificates. For example:

$ keytool -exportcert -keystore test.jks -alias tomcat > exported
$ keytool -importcert -keystore test.jks -file exported

Closes gh-6703
Closes gh-6657

Closes gh-6795

Closes gh-6870

* pr/6872:
  Polish

Closes gh-6872

Update MockitoAopProxyTargetInterceptor to deal with deal with any
existing argument matchers when working with the VerificationMode.

Prior to this commit `@SpyBean` when combined with AOP could not support
argument matchers.

Fixes gh-6871

Update RootUriRequestExpectationManager to only wrap requests when
they cannot be cast to MockClientHttpRequest. This prevents later
ClassCastExceptions from being thrown with @RestClientTests that
define expected body content.

Fixes gh-6845

See gh-6869

This commit improves the JMS health indicator to identify a broken broker
that uses failover. An attempt to start the connection is a good way to
make sure that it is effectively available.

Closes gh-6818

* pr/6651:
  Polish contribution
  Validate Spring Batch database initializer configuration

Closes gh-6651

This commit adds Spring Batch configuration validation that disables
database initializer in case custom table prefix is configured with
default schema.

See gh-6651

* pr/6649:
  Polish contribution
  Validate Spring Session database initializer configuration

Closes gh-6649

This commit adds Spring Session JDBC configuration validation that
disables database initializer in case custom table name is configured
with default schema.

See gh-6649

Update relaxed binding so that names of the form `initSQL` can now
be bound against properties of the form `init-s-q-l`.

Fixes gh-6803

Update our `ResourceHttpRequestHandler` subclass so that the following
warning is no longer displayed:

  "Locations list is empty. No resources will be served unless a
  custom ResourceResolver is configured as an alternative to
  PathResourceResolver."

Fixes gh-6791

* pr/6851:
  Include AuditEvent details in AuditListener

Update `AuthorizationAuditListener` to include `AuditEvent` data if
found.

Closes gh-6851