shaananc/mattermost-docker-with-postfix

1. Create network docker network create nginx-proxy

2. Modify postfix/credentials-smtp.env

3. Modify docker-compose.yml for mattermost-docker changing the letsencrypt and hostname variables

4. Bring up all the containers

5. Modify mattermost config setting the SMTP server as postfix on port 25 (config will be located locally at mattermost-docker/config/config)