[cabfpub] Let's Encrypt

[Gervase Markham]

https://letsencrypt.org/
https://github.com/letsencrypt/
https://github.com/letsencrypt/acme-spec/blob/master/draft-barnes-acme.txt

I'm sure people on the list have things to say :-)

>From Mozilla's perspective, Let's Encrypt is just another CA. If you
have particular questions about how that works, I'd be happy to answer
them, but that sentence basically sums it up.

Gerv