Adds Code of Conduct

[captn3m0]

Nice to have, and a pre-requisite for #224.

Using https://www.contributor-covenant.org as-is. They have a important note on adapting this:

It’s important to understand that simply adopting Contributor Covenant will not prevent conflict or toxicity in your community.
As a leader you are responsible for the safe, fair, and transparent enforcement of your community’s code of conduct. A code of conduct without such enforcement sends a false signal that a community is welcoming and inclusive, which can have a disastrous impact on marginalized or otherwise vulnerable people.
Before you decide to adopt Contributor Covenant, take the time to discuss enforcement with other trusted members of your community. Thoroughly read the Enforcement Guidelines section of the document. If the suggested actions and consequences don’t suit the context of your community, consider moving this section to another document (such as an FAQ or ‘How to Report’ page) and adapting it to your needs.

Since the CoC email comes to me, it isn't perfect - but we can start with this?

[BiNZGi]

Since the CoC email comes to me, it isn't perfect - but we can start with this?

That's okay for me.

[BiNZGi]

All good for me 👍