Update contact for code of conduct

[tephenavies]

Updated to remove de-activated email accounts.

@ljowen I'm not sure if you want to put your new email addresses there, or create a forwarding address - I've assumed the latter. Originally I put 4 email addresses so people could choose who they wanted to report cases to (especially where perceived breaches involved one of the community leaders), but I think most other orgs and communities just have a forwarding address.

Tasks:

• [ ] Create a forwarding address [email protected] (or similar) forwarding to community leaders