Add a EmbeddedServerPortFileWriter which can be used to write server
port information to a file.

Fixes gh-1275
Closes gh-1491

Rename ApplicationPidListener to ApplicationPidFileWriter (keeping the
old class in a deprecated form)

Fixes gh-1673

* spring-boot-1499:
  Add CAMELCASE_TO_HYPHEN in RelaxedNames

Fixes gh-1499

* spring-boot-545:
  Support Jetty HandlerCollection types

Update JettyEmbeddedServletContainer to support HandlerCollection types
in addition to HandlerWrappers.

Fixes gh-545
Closes gh-1597

* spring-boot-amq-mqtt:
  Add ActiveMQ MQTT connection URL auto-detection

Fixes gh-1638

 - Supply auto-configuration for the new indicator
 - As suggested in the pull request, include the free disk space and
   configured threshold in the health details
 - Update the documentation to describe the indicator and its
   two configuration settings
 - Use @ConfigurationProperties to bind the indicator's configuration.
   This should make the changes sympathetic to the work being done
   to automate the configuration properties documentation

Closes gh-1297

See gh-1297

Closes gh-1565

Closes gh-1671

Closes gh-1660

* velo-preferfsa-property:
  Add VelocityProperties.preferFilesystemAccess

Update VelocityProperties to include a preferFilesystemAccess attribute.

Fixes gh-1652

(Cherry picked from commit bebbe92f)
Fixes gh-1633

Conflicts:
	spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/repository/redis/RedisMetricRepository.java

Conflicts:
	spring-boot-dependencies/pom.xml

Closes gh-1474

In addition to requiring the Servlet API to be on the classpath,
MetricFilter requires spring-web to also be on the classpath as it
extends OncePerRequestFilter. This commit updates the auto-configuration
for MetricFilter so that it will be disabled in the absence of a 
dependency on spring-web.

Fixes gh-1664

This commit introduces support for Jackson based XML serialization, using the
new MappingJackson2XmlHttpMessageConverter provided by Spring Framework
4.1. It is automatically activated when Jackson XML extension is detected on the
classpath.

Jackson2ObjectMapperBuilder is now used to create ObjectMapper and XmlMapper
instances with the following customized properties:
 - MapperFeature.DEFAULT_VIEW_INCLUSION is disabled
 - DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES is disabled

JodaModuleAutoConfiguration and Jsr310ModuleAutoConfiguration have been removed
since their behaviors are now handled directly by the ObjectMapper builder.

In addition to the existing @Bean of type ObjectMapper support, it is now
possible to customize Jackson based serialization properties by declaring
a @Bean of type Jackson2ObjectMapperBuilder.

Fixes gh-1237
Fixes gh-1580
Fixes gh-1644

* docs-grammar:
  Fix some grammar issues in docs

Otherwise we had to rely on afterPropertiesSet() being called to
validate and compute the prefix and key (which depend on each
other).

Some weird looking test failures led me to track this down.
If the user changes the prefix for metric names, he probably wanted
to change the keys as welll (otherwise 2 repositories can use the
same key, which is why the test was failing for me). We can do that
in an afterPropertiesSet().