Code is forked from https://github.com/PostgREST/postgrest-heroku
Adds a Dockerfile and a Docker compose file to use PostgREST on Heroku Docker builds directly (without buildpack thus)
Config variables (on Heroku config vars or in your local environnement) should be prexifed by PGRST_DB_
List of fetched variables from environnement to the config file are located in env.list
As on Heroku, the most important is to set the environnement variable $PORT so that listenning port is being transmitted to PostgREST configuration, default to default port 3000 otherwise during build