postfixadmin default admin: root@example.com:toor42

Upgrade 1.x.x => 2.x.x:

• Move SSL certs to data/common/certs/{cert.pem,privkey.pem,chain.pem,fullchain.pem}
• Visit postfixadmin/setup.php to upgrade database

docker-compose down
docker run --rm -v "$(pwd)/data/postgresql/data:/var/lib/postgresql/9.6/data" -v "$(pwd)/data/postgresql/data_new:/var/lib/postgresql/11/data" tianon/postgres-upgrade:9.6-to-11
mv data/postgresql/data data/postgresql/data_old
mv data/postgresql/data_new data/postgresql/data
docker-compose up --build -d