Add test coverage for python scripts

@hillaryj commented on [Tue Oct 27 2020](https://github.com/cisagov/development-guide/issues/31)

This repository has no actual code testing, a `.coveragerc` file, or a `test` workflow, despite containing python scripts in the `project_setup/scripts` directory and requiring `coverage` in [setup.py](https://github.com/cisagov/development-guide/blob/develop/setup.py).

## Acceptance Criteria

- [ ] Add test coverage for scripts
- [ ] Add `.coveragerc` file
- [ ] Integrate with coveralls

---

@mcdonnnj commented on [Wed Oct 28 2020](https://github.com/cisagov/development-guide/issues/31#issuecomment-718095621)

I think we should discuss separating the guide from the tools. It would be nice if the tools were their own package to install instead in my opinion. This would make it easier to add new tools and have a functional CI/CD setup for those tools.

---

@jsf9k commented on [Wed Oct 28 2020](https://github.com/cisagov/development-guide/issues/31#issuecomment-718129494)

> I think we should discuss separating the guide from the tools. It would be nice if the tools were their own package to install instead in my opinion. This would make it easier to add new tools and have a functional CI/CD setup for those tools.

I think this is a grand idea. Do you want to create an issue so we don't lose track of this?