Create CODE_OF_CONDUCT.md

[ricardomiron]

Description

This PR adds a standard code of conduct based on the Contributor Covenant to help facilitate contributions to the project.

Pull Request Checklist

• [x] Short, meaningful title
• [x] Concise description of the pull request
• [ ] Linked to an issue

Coding Standards Checklist

N/A

Documentation Checklist

N/A