Simplified and added setup section

[gulcing]

Pull Request checklist

We appreciate your time and effort to improve the tutorial. Please keep in mind that lesson maintainers are volunteers and it may be some time before they can respond to your contribution.

Before you start

• Read CONTRIBUTING.md.
• Create an issue to discuss your idea. This allows your contributions to be incorporated into the tutorial.

Tasks

• Give this pull request a descriptive title.
• If you are contributing to existing lesson materials, please make sure the content conforms to the Lesson development section in CONTRIBUTING.md and does not contain any spelling or grammatical errors.
• If you are making a new episode, please make sure the content conforms to the Lesson organization and Lesson formatting sections in CONTRIBUTING.md and does not contain any spelling or grammatical errors.
• Preferably Codacy checks pass. Status can be seen below your pull request. If there is an error, click the link to find out why.
• Preview changes on your machine before pushing them to GitHub by running make serve, alternatively make docker-serve. Please see the Previewing your changes locally section in CONTRIBUTING.md for installation instructions.
• All code instructions have been tested.

Closes #159, #173

[LisaBock]

Thanks @gulcing for your contributions!
Could you please separate the different tasks you worked on in different pull request (e.g. one about the link checker and another for the cmorization episode). That would make the review easier. Thanks!