README Updated (#7)

* OpenAPI integration work in progress

* API Gateway updates

* API Gateway support - beta release

* README updated

* README updated

* README updated

* README updated

* README updated

* README updated

* Declaration schema updated, Developer portal alpha release

* Postman collection updated

* Devportal alpha release commit

* Devportal alpha release commit

* Added Developer Portal support

* README updated

* README updated

* README updated

* README updated

* README updated

* README updated

Author: fabriziofiorucci

README.md

@@ -30,7 +30,7 @@ Use cases include:
 
 ```mermaid
 ---
-title: NGINX Declarative API internal architecture
+title: NGINX Declarative API architecture
 ---
 stateDiagram-v2
     DevOps: User