Add contributing guide

Author: orestbida

CONTRIBUTING.md

@@ -0,0 +1,79 @@
+# Welcome to CookieConsent contributing guide
+
+Thank you for investing your time in contributing to this project!
+
+## Documentation
+
+Documentation is available in [cookieconsent/docs](/docs/).
+
+## Getting Started
+
+### Issues
+
+If you encountered a problem, [search if an issue already exists](https://github.com/orestbida/cookieconsent/issues). If no related issues are found, you can [open a new issue via the appropriate issue template](https://github.com/orestbida/cookieconsent/issues/new/choose).
+
+### Make Changes
+
+0. #### Prerequisites
+
+    1. You need to have [node.js LTS](https://nodejs.org/en/download/) installed to test your changes and create the bundled version of the source code.
+
+    2. This project uses `pnpm` to manage the dependencies, which you can install via:
+        ```bash
+        npm i -g pnpm
+        ```
+
+    3. Follow the [Getting started with Github Desktop](https://docs.github.com/en/desktop/installing-and-configuring-github-desktop/overview/getting-started-with-github-desktop) guide.
+
+1. #### Make changes locally
+
+    1. [Fork and clone the repository](https://docs.github.com/en/desktop/contributing-and-collaborating-using-github-desktop/adding-and-cloning-repositories/cloning-and-forking-repositories-from-github-desktop).
+
+    2. [Create a new working branch](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-and-deleting-branches-within-your-repository).
+
+    3. Go to the root of the repo and install all dependencies via:
+
+        ```
+        pnpm install
+        ```
+
+    4. Make the changes, to see your local changes in action, run:
+
+        ```
+        pnpm dev
+        ```
+
+        Note: If you're making changes to the documentation, use `pnpm dev:docs`.
+
+    5. Once you've finished, generate the bundled version via:
+
+        ```
+        pnpm build
+        ```
+    6. Make sure tests are all green:
+
+        ```
+        pnpm test
+        ```
+
+3. Push the changes and [create a Pull Request](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request).
+
+### Pull Request (PR)
+
+1. When creating a new PR, explain briefly what it improves/fixes so that we can easily understand your changes.
+2. Don't forget to [link existing issues](https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue), if you're solving one.
+3. Enable the [allow maintainer edits](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/allowing-changes-to-a-pull-request-branch-created-from-a-fork) checkbox so that the branch can be updated for a merge.
+4. We may ask questions or require changes before a PR is merged.
+5. If everything is clear and sorted out, your PR will be merged! Congratulations 🎉!
+
+#### Note: feature requests
+
+Before creating a feature requests, make sure you "are on the same page" as the maintainer, so that your efforts don't get rejected! A feature request might be rejected if there is no  related issue/discussion.
+
+## Thanks!
+
+Once your PR is merged, your contribution will be available in the next release!
+
+## Questions?
+
+If you have any questions, feel free to [open a new discussion](https://github.com/orestbida/cookieconsent/discussions/new/choose)!