added a basic docker-compose based dev environment

[brendancol]

Issue

Related to #58

Proposed Changes

Add a docker-compose based docker development environment for raster_loader with associated commands in the Makefile.

This PR add the following new commands to the Makefile:

• docker-build: Build necessary stuff.
• docker-start: Start container with docker-compose and attach to logs.
• docker-test: Enter the running raster_loader container and run tests.
• docker-enter: Enter the raster_loader container.
• docker-stop: Stop container

Pull Request Checklist

• I have tested the changes locally
• I have added tests to cover my changes (if applicable)
• I have updated the documentation (if applicable)

Additional Information

I added the docker- prefix to these commands just to keep other existing commands intact, but moving forward we could switch all Makefile commands to interact with the Docker environment and drop the docker- prefix.