chore: add maturity status for each feature

Signed-off-by: Giovanni Liva <[email protected]>

README.md

@@ -4,12 +4,23 @@
 ![Codecov](https://img.shields.io/codecov/c/github/keptn/lifecycle-toolkit?token=KPGfrBb2sA)
 ![goversion](https://img.shields.io/github/go-mod/go-version/keptn/lifecycle-toolkit?filename=operator%2Fgo.mod)
 ![version](https://img.shields.io/github/v/release/keptn/lifecycle-toolkit)
-![status](https://img.shields.io/badge/status-not--for--production-red)
 [![GitHub Discussions](https://img.shields.io/github/discussions/keptn/lifecycle-toolkit)](https://github.com/keptn/lifecycle-toolkit/discussions)
 
 The goal of this toolkit is to introduce a more “cloud-native” approach for pre- and post-deployment, as well as the concept of application health checks.
 It is an incubating project, under the umbrella of the [Keptn Application Lifecycle working group](https://github.com/keptn/wg-app-lifecycle).
 
+Status of the different features:
+
+- ![status](https://img.shields.io/badge/status-stable-brightgreen) Observability
+- ![status](https://img.shields.io/badge/status-alpha-orange) Metrics
+- ![status](https://img.shields.io/badge/status-alpha-orange) Release lifecycle
+
+[//]: # ( alpha ![status](https://img.shields.io/badge/status-alpha-orange)
+[//]: # ( beta ![status](https://img.shields.io/badge/status-beta-yellow)
+[//]: # ( stable ![status](https://img.shields.io/badge/status-stable-brightgreen)
+
+For more info about the features, please refer to our [documentation](./docs/content/en/docs/).
+
 ## Watch the KubeCon 2022 Detroit Demo
 
 Click to watch it on YouTube: