Add initial documents

Add README, licensing information and guides for contributing.

Signed-off-by: Razvan Deaconescu <[email protected]>

CONTRIBUTING.md

@@ -0,0 +1,111 @@
+# Contributing to Internal Computing and Calculus for Advanced Statistics Resources
+
+These are recommendations when contributing to the contents of the internal `CCAS` (Computing and Calculus for Advanced Statistics) repository.
+They consider contributions to and support code (solutions) and other types of content (Markdown) made via Git.
+
+Note that this is an internal repository, for evaluation items (assignments, exam papers, quizzes) that are to be kept private.
+If you plan to contribute to actual public content (lectures, tutorials, demos, assignment statements, assignment skeletons), use the [public (OER) repository](https://github.com/open-education-hub/ccas).
+
+Although meant to be private, these resources adhere to the principles [Open Educational Resources](https://en.wikipedia.org/wiki/Open_educational_resources):
+use them, update them, mix them, contribute back.
+Aim to keep them private, in order to give students a fair and constructive way to solve assignments, quizzes and challenges without access to solutions / answers beforehand.
+
+## First Steps
+
+Some good first steps and best practices when using Git are explained here:
+
+* the Git Immersion tutorial: <https://gitimmersion.com/>
+* the Atlassian tutorial: <https://www.atlassian.com/git/tutorials/learn-git-with-bitbucket-cloud>
+* this blog post on the `ROSEdu Techblog`: <https://techblog.rosedu.org/git-good-practices.html>
+
+## Language
+
+All of our content is developed in English.
+This means we use English for content, support code, commit messages, pull requests, issues, comments, everything.
+
+## Content Writing Style
+
+This section addresses the development of content as Markdown files.
+
+Write each sentence on a new line.
+This way, changing one sentence only affects one line in the source code.
+
+Use the **first person plural** when writing documentation.
+Use phrases like "we run the command / app", "we look at the source code", "we find the flag".
+
+Use the second person for challenges and other individual activities.
+Use phrases like "find the flag", "run this command", "download the tool".
+
+## Images
+
+If images are required, use [draw.io](https://app.diagrams.net/) to create diagrams.
+If using external images / diagram, make sure they use a CC BY-SA license and give credits (mention author and / or add link to the image source).
+
+## Issues
+
+When opening an issue, please clearly state the problem.
+Make sure it's reproducible.
+Add images if required.
+Also, if relevant, detail the environment you used (OS, software versions).
+Ideally, if the issue is something you could fix, open a pull request with the fix.
+
+## Discussions
+
+Use GitHub discussions for bringing up ideas on content, new chapters, new sections.
+Provide support to others asking questions and take part in suggestions brought by others.
+Please be civil when taking part in discussions.
+
+## Pull Requests
+
+For pull requests, please follow the [GitHub flow](https://docs.github.com/en/github/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request-from-a-fork): create a fork of the repository, create your own branch, do commits, push changes to your branch, do a pull request (PR).
+The destination branch of pull requests is the default `master` branch.
+
+Make sure each commit corresponds to **one** code / content change only.
+If there are multiple commits belonging to a given change, please squash the commits.
+
+Also make sure one pull request covers only **one** topic.
+
+### Commits
+
+Before making a commit, configure your name and email locally using:
+
+```bash
+git config --global user.name "Your Name"
+git config --global user.email "[email protected]"
+```
+
+Then make sure the email you've just configured corresponds to the one you have [set on GitHub](https://docs.github.com/en/account-and-profile/setting-up-and-managing-your-personal-account-on-github/managing-email-preferences/adding-an-email-address-to-your-github-account).
+
+After this, make your changes, `git add` them and then commit them using `git commit -s`.
+Always sign your commits using the `-s` / `--signoff` arguments to `git commit`.
+This will add the following line at the end of the commit message:
+
+```text
+Signed-off-by: Your Name <[email protected]>
+```
+
+Notice that the details above are the name and email that you configured earlier.
+
+Now the `git commit` command will open your default editor and ask you to write a commit message.
+Prefix each commit message title with the chapter it belongs to: `software-stack`, `data`, `compute`, `io`, `app-interact` and the component: `lecture` / `lab`.
+An example of a prefix is `compute/lab:`.
+Following the prefix, write a short and expressive title on the first line.
+Use commit messages with verbs at imperative mood: "Add README", "Update contents", "Introduce feature".
+
+Leave an empty line, then add a relevant description of the changes made in that commit.
+This description should include why that change is needed (fixes a bug, improves something that was inefficient, etc.).
+Wrap the lines of this description to 75 characters.
+How a good commit message should look like: <https://cbea.ms/git-commit/>
+Below is an example of a good commit message:
+
+```text
+data/lab: Fix Makefile `CFLAGS` error
+
+`CFLAGS` was incorrectly set to optimise the code to the `-O3` level. This
+caused the function `vulnerable_func()` to be inlined into the caller
+`main()`, making it impossible to overwrite `main()`'s return address with
+that of `vulnerable_func()`. This commit fixes the issue by forcing the
+compiler to not optimise the code by replacing `-O3` with `-O0` in `CFLAGS`
+
+Signed-off-by: Your Name <[email protected]>
+```