Update docs for new extended health support

fixes #930

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

@@ -151,10 +151,10 @@ To provide custom health information you can register a Spring bean that impleme
 	import org.springframework.stereotype.Component;
 
 	@Component
-	public class MyHealth implements HealthIndicator<String> {
+	public class MyHealth implements HealthIndicator {
 
 		@Override
-		public String health() {
+		public Health health() {
 			// perform some specific health check
 			return ...
 		}
@@ -170,6 +170,16 @@ Redis, MongoDB and RabbitMQ.
 Spring Boot adds the `HealthIndicator` instances automatically if beans of type `DataSource`,
 `MongoTemplate`, `RedisConnectionFactory`, `RabbitTemplate` are present in the `ApplicationContext`.
 
+Besides implementing custom `HealthIndicator`s and using out-of-box {sc-spring-boot-actuator}/health/Status.{sc-ext}[`Status`]
+types, it is also possible to introduce custom `Status` types for different or more complex system 
+states. In that case a custom implementation of the {sc-spring-boot-actuator}/health/HealthAggregator.{sc-ext}[`HealthAggregator`]
+interface needs to be provided or the default implementation has to be configured using the 
+`health.status.order` configuration property. 
+
+Assuming a new `Status` with code `FATAL` is being used in one of your `HealthIndicator` 
+implementations. To configure the severity or order add the following to your application properties:
+`healt.status.order: FATAL, DOWN, UNKOWN, UP`.
+
 
 
 [[production-ready-application-info]]