Add a TestNG sample that also demonstrates @WebIntegrationTest.

See gh-2135

Add `@WebIntegrationTest` which is similar to `@IntegrationTest` and
`@WebAppConfiguration`. The annotation using Spring's `@BootstrapWith`
annotation rather than `@TestExecutionListeners` which allows it to
work when `@TestExecutionListeners` (even ServletTestExecutionListener)
are declared on the test class.

This annotation is particularly useful for TestNG users that extend
Spring's `AbstractTestNGSpringContextTests` class.

Fixes gh-2299
See gh-1956
See gh-2135

Include more details in the message including the class being bound
and the prefix from the annotation.

Fixes gh-2246

Update ConfigFileApplicationListener to make some of the static final
constants public.

Fixes gh-2253

* gh-2287:
  Don't fail build on merge failure

Be more lenient when processing additional metadata json files.

Fixes gh-2287
Closes gh-2288

Update ConfigurationMetadataAnnotationProcessor to find the additional
metadata json file using createResource rather than getResource. Prior
to this commit the file could be skipped when multiple files were
contained on the classpath.

Fixes gh-2271

Update InMemoryAuditEventRepository to consider the date when searching
for events. Also switch to a circular buffer implementation and update
the capacity to limit the total number of items rather than limiting
per principal.

Fixes gh-2291

Update EmbeddedWebApplicationContext to store then restore any existing
web scopes that may have been registered. This allows custom web scopes
to be registered in an ApplicationContextInitializer.

Fixes gh-2082

Closes gh-2232

Closes gh-2232

Update CONTRIBUTING to include the project lead names that can be used.

The "Customizing ConfigurableEmbeddedServletContainer directly"
section should use `HttpStatus.NOT_FOUND` and not `HttpStatus.404` in
the sample code.

Fixes gh-2258

Replace various for loops which add items to collections with calls
to Collections.addAll(...).

Fixes gh-2277

Change the LoggingSystem load order so that Log4J2 has a higher priority
than Log4J. Also add system property support to allow a specific system
to be used.

Fixes gh-2274

See gh-2180

Conflicts:
	spring-boot-dependencies/pom.xml

Update spring-boot-dependencies to include all Jetty modules. The helps
to prevent issues when modules are pulled in transitively (for example
via solr).

Fixes gh-2180

Conflicts:
	spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jmx/JmxAutoConfiguration.java
	spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jmx/ParentAwareNamingStrategy.java
	spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jmx/JmxAutoConfigurationTests.java

Fix ParentAwareNamingStrategy to set ObjectName properties for the
'identity' and 'context' attributes. Also update JmxAutoConfiguration
to ensure that the ParentAwareNamingStrategy is created in each context
and that the `mbeanExporter` bean is created. Prior to this commit the
nested @EnableMBeanExport class always meant that the mbeanExporter
condition never matched.

Fixes gh-2243

Conflicts:
	spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/WebMvcAutoConfigurationTests.java

Update WebMvcAutoConfiguration to ensure than the viewResolver bean
is not created if a user defined ContentNegotiatingViewResolver bean
is defined.

Fixes gh-2269

Update IntegrationTest Javadoc to remove the "fully leaded"
colloquialism.

See gh-2272

* pull2265:
  Fix global `endpoints.enabled` property support

Update AbstractEndpoint to correctly support the `endpoints.enabled`
property. Also fix EnvironmentEnpoint which would previously prevent
the Environment from being set.

Fixes gh-2264
Closes gh-2265

* pull2266:
  Add application version info to JAR manifest

Update maven-jar-plugin configuration in spring-boot-starter-parent
with `addDefaultImplementationEntries` so that implementation versions
are included by default.

Fixes gh-2266

* docs-health-builder:
  Update custom HealthIndicator documentation

Update the custom HealthIndicator documentation to use the build()
method rather than the old mechanism.

Fixes gh-2270

(cherry picked from 80d55c47)
Closes gh-2255

(cherry picked from commit 300e570f)
Fixes gh-2261
See gh-1259

Conflicts:
	spring-boot/src/test/java/org/springframework/boot/bind/RelaxedPropertyResolverTests.java

Closes gh-2262

Conflicts:
	spring-boot-dependencies/pom.xml