Update the BasicErrorController so that it no longer needs to implement
@ControllerAdvice or have an @ExceptionHandler method.

A new ErrorAttributes interface is now used to obtain error details,
the DefaultErrorAttributes implementation uses a
HandlerExceptionResolver to obtain root exception details if the
`javax.servlet.error.*` attributes are missing.

This change also removes the need for the extract(...) method on
ErrorController as classes such as WebRequestTraceFilter can
now use the ErrorAttributes interface directly.

See gh-839, gh-538
Fixes gh-843

Conflicts:
	spring-boot-dependencies/pom.xml

Closes #841

We might need to revisit this to allow more fine-grained
control by users, but it seems like a sensible default.
The BasicErrorController now uses both of the deafult strategies
(ResponseStatusExceptionResolver and DefaultHandlerExceptionResolver)
from Spring MVC to try and determine an appropriate response.

Fixes gh-839

Temporarily remove the Spring Security BOM import as version numbers
for the imported projects don't automatically get resolved by the
gradle plugin.

See gh-838

Add replace goals to update the Spring Boot version in the gradle and
ant samples during the release process.

Fixes gh-425

Fix maven warnings caused by missing version information on the
root POM.

* _data-platform:
  Read data-{platform}.sql in addition to data.sql

Update DataSourceAutoConfiguration to read platform specific `data.sql`
files in the same way as `schema.sql` files.

Fixes gh-837

Rename the rabbitHealthIndicator bean which was accidentally named
redisHealthIndicator.

Extract WebMvcProperties from WebMvcAutoConfiguration and also
update conditionals to use @ConditionalOnProperty.

Add `spring.resources.add-mappings` allowing users to configure if
resource mappings should be added or not.

Fixes gh-804

Update ConditionalOnProperty to optionally support relaxed form names.

Fixes gh-835

Update reference documentation to make it clearer why you might not
always want to use the spring-boot-starter-parent.

Fixes gh-774

Update to latest release of Spring Plugin and provide dependency
management for all of its modules

Closes #802

Add an explicit dependency to `hamcrest-core` in the
`spring-boot-starter-test` POM. This prevents version 1.1 from
accidentally being pulled in via junit.

Fixes gh-810

Reorder dependencies so that they're consistently in alphabetical
order

Update @ConditionalOnProperty so that properties that are present but
contain the value `false` are not considered a match.

Fixes gh-812

Fixes gh-811

Rework HealthIndicator support

* conditionalOnPropertiesPresent:
  Add @ConditionalOnProperty annotation

Add @ConditionalOnProperty which enables conditional bean creation when
all required properties are defined in the Environment.

Fixes gh-812

Add a `versionManagement` gradle configuration which can be used to
provide alternative version meta-data. Primarily added so that the
Spring IO platform can provide version overrides without causing a
cyclic build dependency.

Fixes gh-750

Temporarily remove the spring-data release train BOM since it cannot
be resolved until it is published to maven central.

The previous solution of adding an additional repository has been
reverted as it will pollute POMS for users that inherit from the
spring-boot-starter-parent POM.