Loot at the docker-compose.yml file for an example of how to use this image.
If TESTING is set to true, the certificate will be issued by the Let's Encrypt staging server. This is useful for testing, but you should not use it in production.
if LETSENCRYPT_WILDCARD is set to true, the certificate will be issued for the wildcard domain *.yourdomain.duckdns.org. This is useful if you want to use the same certificate for multiple subdomains but not for the base domain.
Heavily inspired by https://github.com/maksimstojkovic/docker-letsencrypt