Install Docker.

Dockerfile

@@ -9,7 +9,7 @@ LABEL com.example.vendor="PARAGON Executive Service GmbH" \
 
 RUN echo "===> Adding GIT..." && \
     apt-get update -y && \
-    apt-get install -y -q git && \
+    apt-get install -y -q git docker-ce && \
     echo "Completed"