Expanded command line interface

• expand command line interface for allow for future growth in feature set
• internal refactoring

Incremental improvement v0.0.1-alpha5

• new CI workflows: run unit tests, release to pypi, release to dockerhub
• new container available on dockerhub to run the tool without any further installation
• new default: when looking for container image, will now search through docker images without trying to docker pull
• new --pull command line option to allow pulling images if they are not up to date or do not exist in docker images

Initial prototype

Initial proof of concept that looks at each layer and reconstructs shell commands that created it.
Differentiates between RUN shell commands and docker commands.