Add Quality gate badge to README

README.md

@@ -1,4 +1,4 @@
-SonarQube [![Build Status](https://travis-ci.org/SonarSource/sonarqube.svg?branch=master)](https://travis-ci.org/SonarSource/sonarqube)
+SonarQube [![Build Status](https://travis-ci.org/SonarSource/sonarqube.svg?branch=master)](https://travis-ci.org/SonarSource/sonarqube) [![Quality Gate Status](https://sonarcloud.io/api/project_badges/measure?project=org.sonarsource.sonarqube%3Asonarqube&metric=alert_status)](https://sonarcloud.io/dashboard?id=org.sonarsource.sonarqube%3Asonarqube)
 =========
 
 Continuous Inspection