using IP Geolocation Timezone API: https://ipgeolocation.io/ and Axios: https://axios-http.com/docs/intro
time is returned in ISO-8601 format
- if no parameter is passed local time based on the IP is returned
- if timezone parameter is passed in the form of a CLDR (https://cldr.unicode.org/) standardized timezone name, the current time in this timezone is returned
create with: docker build . -t <image_name>
start with: docker run -dit --name <container_name> <image_name>
exec with: docker exec -it <container_id> bash
send request with: node zeitservice <timezone>