create CONTRIBUTING.md

[LongLiveCHIEF]

Need to have some information and documentation put together for those who want to contribute. A CONTRIBUTING.md file is standard, and will integrate with GitHub and automatically be shown to those opening issues or pull requests.

A CONTRIBUTING.md file typically covers:

• how to set up a development environment
• requirements that must be met for a pull request
• information on how to communication with other collaborators or maintainers
• any rules or agreements you want contributors to follow
• how to submit security vulnerability findings privately (this is very important)

GitHub's docs have some good example CONTRIBUTING files

[LongLiveCHIEF]

Right now, it seems as if the best way to develop your contribution locally, is to follow the instructions for the self-hosting installation?

Anything else that would be important if you're actively using that environment as a development/debugging environment? Any additional tools or settings that would be recommended?