Document auto-configuration support for Spring HATEOAS

Closes gh-2426

Author: wilkinsona

spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc

@@ -1150,6 +1150,22 @@ behaviour by setting `com.ibm.ws.webcontainer.invokeFlushAfterService` to `false
 
 
 
+[[boot-features-spring-hateoas]]
+==== Spring HATEOAS
+If you're developing a RESTful API that makes use of hypermedia, Spring Boot provides
+auto-configuration for Spring HATEOAS that works well with most applications. The
+auto-configuration replaces the need to use `@EnableHypermediaSupport` and registers a
+number of beans to ease building hypermedia-based applications including a
+`LinkDiscoverer` and an `ObjectMapper` configured to correctly marshal responses into
+the desired representation. The `ObjectMapper` will be customized based on the
+`spring.jackson.*` properties or a `Jackson2ObjectMapperBuilder` bean if one exists.
+
+You can take control of Spring HATEOAS's configuration by using
+`@EnableHypermediaSupport`. Note that this will disable the `ObjectMapper` customization
+described above.
+
+
+
 [[boot-features-jersey]]
 === JAX-RS and Jersey
 If you prefer the JAX-RS programming model for REST endpoints you can use one of the