adopt covenant code of conduct?

i don't think we have had harrassment problems yet in Monkeysign (if we have, feel free to contact me directly at anarcat@debian.org, i accept PGP-encrypted email - if it is about me, you should probably contact @dkg or another member as well).

but it's exactly at about that time that it is good to set preemptive code of conduct policies, before problems happen. it shows a clear stance against abusive or discriminatory behaviour, and makes people feel more welcome.

i have just found out about the contributor covenant code of conduct. i still need to review it in details, but I would like to adopt it for monkeysign. here is the markdown version we could include in the contributor and maybe even README notes.

it feels weird to take this decision on my own, so I would like to get feedback from others as well. @lavamind, @dkg, opinions?