List.cons function available to the List module users

[dev-danilosilva]

Because in Elm everything is simple and intuitive in a certain way, List.cons should be part of the functions available to the users besides the (::) function.
It happens in some parts of the language standard libraries. For example, I can construct a tuple by using the literal form (x, y) or by calling the function Tuple.pair x y and both ways are OK and does not decrease the quality of the user code when using one or another.

[github-actions]

Thanks for suggesting these code changes. To set expectations:

• Pull requests are reviewed in batches, so it can take some time to get a response.
• Smaller pull requests are easier to review. To fix nine typos, nine specific issues will always go faster than one big one. Learn why here.
• Reviewers may not know as much as you about certain situations, so add links to supporting evidence for important claims, especially regarding standards for CSS, HTTP, URI, etc.

Finally, please be patient with the core team. They are trying their best with limited resources.