Restructure README.md and add CONTRIBUTING.md #251

- Created CONTRIBUTING.md with welcoming content for new contributors
- Restructured README.md from 507 to 120 lines (76% reduction)
- Converted verbose project descriptions to scannable table format
- Added prominent Contributing section near the top
- Organized projects into logical categories (Core Tools, Inspectors, Libraries, Other Tools)
- Improved visual hierarchy with GitHub-style alerts
- Maintained all essential information while improving readability
- Verified documentation build succeeds

This makes the README more beginner-friendly and less overwhelming for newcomers while preserving all project information in a more accessible format.

Signed-off-by: Gyan Ranjan Panda <gyanranjanpanda@gmail.com>

Author: Mac

CONTRIBUTING.md

@@ -0,0 +1,91 @@
+# Contributing to AboutCode
+
+Welcome! We're excited that you're interested in contributing to AboutCode. This document will help you get started with contributing to our projects.
+
+## Quick Start for New Contributors
+
+1. **Explore Our Projects**: Browse through our [project list](README.md#projects) to find something that interests you
+2. **Find an Issue**: Look for issues labeled `good first issue` or `help wanted` in the repository you're interested in
+3. **Join the Community**: Introduce yourself in our [Gitter chat](https://app.gitter.im/#/room/#aboutcode-org_discuss:gitter.im) or on [Slack](https://join.slack.com/t/aboutcode-org/shared_invite/zt-1paqwxccw-IuafuiAvYJFkTqGaZsC1og)
+4. **Read the Documentation**: Check out our [full documentation](https://aboutcode.readthedocs.io/en/latest/) for detailed guides
+
+## Communication Channels
+
+- **Gitter Chat**: [aboutcode-org#discuss](https://app.gitter.im/#/room/#aboutcode-org_discuss:gitter.im)
+- **Slack**: [Join our workspace](https://join.slack.com/t/aboutcode-org/shared_invite/zt-1paqwxccw-IuafuiAvYJFkTqGaZsC1og)
+- **Weekly Meetings**: We hold weekly community calls. See [meeting minutes](https://github.com/aboutcode-org/aboutcode/wiki/MeetingMinutes) for details
+
+## How to Contribute
+
+### Reporting Issues
+
+If you find a bug or have a feature request:
+- Check if the issue already exists
+- If not, create a new issue with a clear title and description
+- Include steps to reproduce (for bugs) or use cases (for features)
+
+### Contributing Code
+
+1. **Fork the repository** you want to contribute to
+2. **Create a branch** for your changes: `git checkout -b fix-issue-123`
+3. **Make your changes** following the project's coding standards
+4. **Write tests** if applicable
+5. **Commit your changes** with a clear commit message (see our [commit message guidelines](https://aboutcode.readthedocs.io/en/latest/contributing/writing_good_commit_messages.html))
+6. **Push to your fork** and submit a pull request
+
+### Contributing Documentation
+
+Documentation improvements are always welcome! You can:
+- Fix typos or clarify existing documentation
+- Add examples or tutorials
+- Improve the structure and organization
+
+Documentation is built using Sphinx. To build locally:
+```bash
+make docs
+```
+
+## Development Guidelines
+
+### Commit Messages
+
+We follow specific commit message conventions:
+- Use imperative mood ("Add feature" not "Added feature")
+- Keep the subject line under 50 characters
+- Reference issue numbers when applicable (#123)
+- Sign off your commits with `Signed-off-by: Your Name <your.email@example.com>`
+
+For detailed guidelines, see our [commit message documentation](https://aboutcode.readthedocs.io/en/latest/contributing/writing_good_commit_messages.html).
+
+### Testing
+
+Before submitting a pull request:
+- Run existing tests to ensure nothing breaks
+- Add new tests for new functionality
+- Ensure all tests pass
+
+See the [testing documentation](https://aboutcode.readthedocs.io/en/latest/contributing/testing.html) for more details.
+
+## Code of Conduct
+
+We are committed to providing a welcoming and inclusive environment. Please read our [Code of Conduct](CODE_OF_CONDUCT.rst) before participating.
+
+## Getting Help
+
+- **Documentation**: Start with our [ReadTheDocs](https://aboutcode.readthedocs.io/en/latest/)
+- **Chat**: Ask questions on [Gitter](https://app.gitter.im/#/room/#aboutcode-org_discuss:gitter.im) or [Slack](https://join.slack.com/t/aboutcode-org/shared_invite/zt-1paqwxccw-IuafuiAvYJFkTqGaZsC1og)
+- **Issues**: Open an issue in the relevant repository if you need help with something specific
+
+## Additional Resources
+
+- [Full Contributing Guide](https://aboutcode.readthedocs.io/en/latest/contributing.html)
+- [Documentation Contribution Guide](https://aboutcode.readthedocs.io/en/latest/contributing/contrib_doc.html)
+- [GSoC Information](https://github.com/aboutcode-org/aboutcode/wiki)
+
+## License
+
+By contributing to AboutCode, you agree that your contributions will be licensed under the Apache License 2.0.
+
+---
+
+Thank you for contributing to AboutCode! Your efforts help make open source software safer and more transparent for everyone.