feat: implementation of Policy service

.gitlab-ci.yml

deploy_in_kubernetes.sh

manifests/policyservice.yaml

src/policy/.dockerignore

src/policy/.env.example

src/policy/.gitignore

src/policy/.gitlab-ci.yml

src/policy/.java-version

src/policy/.mvn/wrapper/MavenWrapperDownloader.java

src/policy/.mvn/wrapper/maven-wrapper.jar

src/policy/.mvn/wrapper/maven-wrapper.properties

src/policy/Dockerfile

src/policy/README.md

src/policy/mvnw

src/policy/mvnw.cmd

src/policy/pom.xml

src/policy/src/main/docker/Dockerfile.multistage.jvm

...olicy/src/main/java/eu/teraflow/policy/PolicyGateway.java

...y/src/main/java/eu/teraflow/policy/PolicyGatewayImpl.java

...olicy/src/main/java/eu/teraflow/policy/PolicyService.java