Chore: Integrate REUSE tool in README (#33)

Author: SebastianWolf-SAP

.reuse/dep5

@@ -28,5 +28,5 @@ Disclaimer: The code in this project may include calls to APIs (“API Calls”)
  For any usage of built Docker images please make sure to check the licenses of the artifacts contained in the images.
 
 Files: **
-Copyright:  2017-2020 SAP SE or an SAP affiliate company and contributors
+Copyright:  2017-2021 SAP SE or an SAP affiliate company and contributors
 License: Apache-2.0

README.md

@@ -1,5 +1,7 @@
 # Node Browsers Image
 
+[![REUSE status](https://api.reuse.software/badge/github.com/SAP/devops-docker-node-browsers)](https://api.reuse.software/info/github.com/SAP/devops-docker-node-browsers)
+
 This [_Dockerfile_](https://docs.docker.com/engine/reference/builder/) can be used in _Continuous Delivery_ (CD) pipelines for SAP development projects.
 The image is optimized for use with project ["Piper"](https://github.com/SAP/jenkins-library) on [Jenkins](https://jenkins.io/).
 Docker containers simplify your CD tool setup, encapsulating tools and environments that are required to execute pipeline steps.
@@ -43,3 +45,7 @@ The given tag **must** exist in the [node](https://hub.docker.com/_/node) base i
 ## Usage
 
 See this [blog post](https://blogs.sap.com/2017/12/11/sap-s4hana-cloud-sdk-end-to-end-tests-against-secured-applications/) for usage of this image in a Jenkins pipeline based on `ppiper/jenkins-master`.
+
+## Licensing
+
+Copyright 2017-2021 SAP SE or an SAP affiliate company and devops-docker-node-browsers contributors. Please see our [LICENSE](LICENSE) for copyright and license information. Detailed information including third-party components and their licensing/copyright information is available [via the REUSE tool](https://api.reuse.software/info/github.com/SAP/devops-docker-node-browsers).