Concept/map reduce

[JaumeAmoresDS]

Added conceps for higher-order functions map and reduce

[github-actions]

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[bobbicodes]

This is great, thanks! I'll probably only have minor suggestions

[bobbicodes]

I'm thinking maybe the introduction pages could be made smaller. Since the purpose of having a separate Introduction and About page is for the former to contain just enough to get them started, while the About pages are more comprehensive.

(This is more of a statement on how thorough you made them than a criticism)

[JaumeAmoresDS]

@bobbicodes would it be good like this? I removed the last two sections of each introduction.md, but kept them in about.md

[bobbicodes]

Yes, that's perfect :)

[bobbicodes]

While we are touching things related to these new concepts, it just occurred to me that the tree will be affected significantly due to their introduction. In other words, someone will need to go through the practice exercises in the root config.json and add map and/or reduce to the prerequisites and practices arrays to the exercises as appropriate.

I expect there to be a lot of relevant exercises.

This could be done in a later PR however. It's kind of a big job because you have to go through each one and decide whether the concept is essential to solving it.

[JaumeAmoresDS]

I might be able to do it, although I think it will take a bit of time. The thing is that I am not familiar with the exercises, since I did very few so far. I'm also a newbie in clojure, which makes it a bit more challenging, although this might not be an issue if I am guided through the PR review process.

[bobbicodes]

No worries, just thinking ahead :)