Add example dockerfile for connecting to remote sql databases.

[parrotcar00]

Hi, I was looking for a Uber cadence postgres example where the postgres instance is not running in a docker image beside it.
In such a case, you would have to provide the url of the remote postgres instance along with the TLS cert files when running uber cadence docker.
The docker-compose-postgres.yml file does not capture this scenario of connecting to a remote postgres instance.
Would it be possible to add another docker file which shows how to connect to a remote postgres instance specifying the tls params that are needed?