Add "key" to default keys that will be sanitized. fixes #1027

- Log to the correct class
- Set Auto-configure after Thymeleaf hint on main class instead of
  internal static class
- Use 'thymeleafViewResolver' bean name instead of class for
  conditional bean checks
- Fix class name in properties documentation

Fixes gh-1052

Also added additional test to verify behaviour.

Fixes gh-1039

Anywhere that an MBeanServer is needed it should be
created @Conditionally, so that user can exclude the
JmxAutoConfiguration and still get the other JMX
behaviours automatically.

I decided to go with both approaches (make the autoconfig for
repositories @ConditionalOnMissingBean(RepositoryFactoryBeanSupport),
so the first one wins; and also make them conditional on
spring.data.*.repositories.enabled=true. The ordering problem
is still there really (it's not defined which repositories will
be created by the autoconfig), so if a user is going to have
2 repository implementations on the classpath, he is going to
have to either choose one to disable, or manualy @Enable* the
other one.

Fixes gh-1042

See gh-1047

Update all starter POMs to remove commons-logging dependencies that are
not longer required when using the Spring Boot Gradle plugin.

Mainly reverts code from 196f92bd

See gh-1047

Update the Spring Boot Gradle plugin to automatically apply exclude
rules to dependencies.

See gh-1047

Update spring-boot-dependency-tools to support transitive excludes.
Transitive excludes are useful with Gradle which considers each
dependency independently (see GRADLE-3061).

Transitive excludes are supported by parsing the dependency-tree file
from spring-boot-versions.

See gh-1047

Update spring-boot-versions to generate a dependency-tree file and
attach it as an artifact. The file is generated by creating a temporary
POM and calling the invoker plugin.

The spring-boot-versions POM now depends on all spring-boot-starter-*
POMs to ensure that they have been installed before the dependency
tree is processes.

See gh-1047

Refactor dependency-tools to restore API compatibility with Spring
Boot 1.0. This should reduce reflection hacks that tools such as Gretty
would otherwise have to make.

See gh-1035

Update Spring Mobile support with the following changes:
- Apply source formatting
- User lowercase property prefixes
- Use dashed notation when accessing properties
- Inline some constants

See gh-1049

@PropertySources *can* and should be added in the slot
after the application.properties (code that is part of the
application should have lower precedence than external
configuration).

Fixes gh-1044

(Leaving the docs changes for later)

Fixes gh-1049

* pull1050:
  Add ProviderSignInController for Spring Social

Update SocialWebAutoConfiguration to add a ProviderSignInController.
Also fix default UserIdSource.

Fixes gh-1050

- Upgrade Spring Mobile dependency to 1.1.2
- Rename SitePreferenceAutoConfiguration "enabled" property
- Add Auto-configuration for LiteDeviceDelegatingViewResolver
- Update docs

Fixes gh-1049

Extract common "depends on" functionality to a new
EntityManagerFactoryDependsOnPostProcessor class.

Apply consistent formatting.

Fix issue with Flyway location detection.

Apply formating and simplify the condition implementation. Delegate
to Spring's JdkVersion class to obtain the running version.

Apply consistent styling and edit a few section for clarity.

Rename a few classes and methods relating to DataSourceInitialization
and update the DataSourceInitializedPublisher to check for Hibernate
settings.

It was doing scary things (like starting elasticsearch, hornetq etc).
There's still an outstanding question about why the context was
not being properly closed in such a scenario (maybe one of those
embedded servers lurking on a background thread?).

See gh-1034

They all want to create an MBeanServer and when that happens
user sees no MBeans, or sometimes just one set (Spring Core,
Spring Integration or Spring Boot). To harmonise them we
create a @Bean of type MBeanServer and link to it in the
other autoconfigs

Fixes gh-1046

We now register the Jackson JodaTime module with Jackson ObjectMappers
if it is on the classpath. We also register the JSR-310 module if it's
on the classpath and the application is running Java 8 or better.

Extracted the Jackson specific configuration previously residing in
HttpMessageConvertersAutoConfiguration into a JacksonAutoConfiguration
class.

Added the Jackson JSR-310 module as a managed Boot dependency.

Added a new @ConditionalOnJava annotation that allows to conditionally
enable configuration based on the Java version that is running. 

The annotation currently supports two modes of restricting Java versions:
the default mode checks for a Java version equal or better than the
requested one. Beyond that it can be configured to only match if Java
version is older than the configured one.

We've had problems with the starters when used with Gradle. They have
been pulling in commons-logging (#987) and the wrong version of Spring
(#1028) due to Gradle's different exclusion and dependency resolution
semantics.

This commit adds some integration tests that use Gradle's tooling API
to take each starter in turn and build a Gradle project that depends
upon it. The build looks at the transitive dependencies and checks
that neither commons-logging nor any Spring modules with the wrong
version are present.

Closes #1036