Add new template based on dune and melange

[kevgathuku]

Following up on the conversation regarding the migration to a supported toolkit:
https://forum.exercism.org/t/progress-on-migrating-to-rescript/15829

This is just a demo of what I envision a typical exercise would look like if it was based on Melange + Dune

The idea of adding the template first is to show a minimal but working setup.

It compiles to JS and includes a testing setup and also a Makefile to avoid some of the manual steps.

Let's evaluate this approach and see where it goes. Happy to hear your feedback 😄

Also let me know if it would be better to target another branch other than main which would help to do the migration gradually

[github-actions]

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[github-actions]

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[github-actions]

This is an unmaintained repository.

Cross-track maintainers - feel free to merge.

[kevgathuku]

I'll remove more unnecessary stuff and just keep it as minimal as possible like the existing template.

Also what's the tag to skip running CI for each commit? 😅

[kevgathuku]

The template is now ready.

Changes:

• Keep the existing npm-based commands / workflow, including running tests with jest
• Update the new-exercise script

Using bin/new-exercise.sh will now generate a fully functional exercise based on melange, including working tests.

[vaeng]

LGTM

[vaeng]

Too bad we have no checks on this track to see if everything works fine. Maybe a new project @kevgathuku ;)

[kevgathuku]

Too bad we have no checks on this track to see if everything works fine. Maybe a new project @kevgathuku ;)

Definitely. There are some changes I should undo here but will probably do that in a new PR as this one is already approved 😃

One idea is to create some test exercises with the new template, and ensure they can be built / run by the test runner https://github.com/exercism/reasonml-test-runner

[kevgathuku]

Made the last changes to the template and now there's no more changes I expect to make here.

Next I'll move on to this:

Create some test exercise with the new template, and ensure they can be built / run by the test runner exercism/reasonml-test-runner