CODE_OF_CONDUCT: mention individual project-leader emails

CODE_OF_CONDUCT: mention individual project-leader emails

It's possible that somebody on the project committee is the subject of a
complaint. In that case, it may be useful to be able to contact the
other members individually, so let's make it clear that's an option.

This also serves to enumerate the set of people on the committee. That
lets you easily _know_ if you're in the situation mentioned above. And
it's just convenient to list who's involved in the process, since the
project committee list is not anywhere else in the repository.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>