Convert code of conduct to markdown for Github

[ammaraskar]

Trivial patch, doesn't need issue or news entry

[matrixise]

just one question, why do you convert it to markdown? the document already exists in ReST...

[ammaraskar]

Github only accepts code of conducts in markdown: https://help.github.com/articles/adding-a-code-of-conduct-to-your-project/

I think this allows them to show up in various places in the interface like this:

and visible to this api https://developer.github.com/v3/codes_of_conduct/

[matrixise]

ok, but they don't specify only markdown, they use markdown, that could be .rst

but ok

[ammaraskar]

No it can't, see here: https://github.com/python/cpython/community

[JulienPalard]

Hi @ammaraskar thanks for noticing and fixing!