Merge pull request #3 from NathanTarbox/master

Working against 1.1.14

added additional Docker learning resources

Added reference doc to Docker Hub postgres

Additions needed for setting up Postgres backend setup

fixed url and added clarifications

Fixed tree formatting

Moved the Docker Compose file to the root project file as this is probably where most people would expect it to be

Dockerized the example using Docker Compose and also used named volume instead

Shortened and clarified reason for using lazy form

Added why I prefer dict form for repository return type

Added clarifications to the readme

Added section on code orgnanization

Added Dockerized version and added clarifications in readme

Created Dockerized version, but without dagster-daemon running. Will add scheduler when I figure out docker-compose