Fold WebFlux and MVC support note into the Overview

The standalone NOTE calling out WebFlux and MVC support was tied to
"version 3.0 and later", a qualifier that no longer means anything on
a branch that starts at 5.1.x. Move the statement into the Overview
paragraph where it belongs, drop the stale version qualifier, and
link Spring WebFlux and Spring MVC to their reference docs.

Signed-off-by: Roy Clarkson <roy.clarkson@broadcom.com>

Author: royclarkson

README.adoc

@@ -4,7 +4,7 @@ image:https://github.com/spring-cloud/spring-cloud-open-service-broker/actions/w
 
 = Overview
 
-Spring Cloud Open Service Broker is a framework for building https://projects.spring.io/spring-boot/[Spring Boot] applications that implement the https://www.openservicebrokerapi.org/[Open Service Broker API].
+Spring Cloud Open Service Broker is a framework for building https://projects.spring.io/spring-boot/[Spring Boot] applications that implement the https://www.openservicebrokerapi.org/[Open Service Broker API]. Both https://docs.spring.io/spring-framework/reference/web/webflux.html[Spring WebFlux] and https://docs.spring.io/spring-framework/reference/web/webmvc.html[Spring MVC] web frameworks are supported in Spring Cloud Open Service Broker.
 
 == Version Compatibility
 
@@ -22,9 +22,6 @@ The following table describes the version compatibility matrix for the various r
 |3.6.x |2.16 |2.7.x |5.3.x|8
 |===
 
-[NOTE]
-Spring WebFlux and Spring MVC are both supported in version 3.0 and later
-
 == Getting Started
 
 See the https://spring.io/projects/spring-cloud-open-service-broker/[project site] and https://docs.spring.io/spring-cloud-open-service-broker/docs/current/reference/[reference documentation] to get started building a service broker using this framework.