Update README.md

README.md

 # maven3-jdk-11-swt
 
-Extends the default maven:3-jdk-11 docker image to add support for SWT related tests in a gitlab pipeline.
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+Extends the default maven:3-jdk-11 docker image to add support for SWT related tests in a gitlab pipeline.
+
+
+## Usage
+
+Use the image in the gitlab-ci.yml
+
+     image: gitlab.link-intersystems.com:5050/open-source/docker/maven3-jdk-11-swt:latest
+
+Start the build process using `xvfb-run`. E.g. for maven
+
+     xvfb-run mvn $MAVEN_CLI_OPTS -Pdist install -s ci_settings.xml
+
+
+