Added file service port forwarding to Docker image

Dockerfile

 FROM openjdk:14-jdk-alpine
 ARG JAR_FILE=target/vospace.jar
 COPY ${JAR_FILE} vospace.jar
-ENTRYPOINT ["java","-jar","/vospace.jar"]
+
+RUN apk add socat
+ADD docker-entrypoint.sh /
+RUN chmod +x /docker-entrypoint.sh
+ENTRYPOINT ["/docker-entrypoint.sh"]

docker-entrypoint.sh

+#!/bin/sh
+
+if [ ! -z "$FILE_SERVICE_PORT" ]; then
+    socat TCP-LISTEN:$FILE_SERVICE_PORT,fork TCP:vospace_file_service:$FILE_SERVICE_PORT &
+fi
+
+java -jar /vospace.jar