Database connection not working in Docker release

Docker release throws the following exception, see [here](https://stackoverflow.com/questions/37482716/using-docker-to-launch-web-app-cant-connect-to-postgresql-db) to fix.

```
org.postgresql.util.PSQLException: Connection to localhost:5432 refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.
```