Add examples/new chapter on creating code to solve a more complex problem

[ehumph]

This was a question brought up during the presentation of this course to ITN on 6/8/2023. The valid point was made that the multistep programming example (creating a game of blackjack) is solving a task that's been done before and has known rules and steps. There's interest in an example or chapter on how to solve a completely unknown problem, since those are the sorts of things we do in science.

Perhaps we need a chapter on advanced code writing? I still think there's merit in having people do something that they know can be solved as a first pass. It is easier to understand the necessary steps and how it might work when you're familiar with the end product.