* nginx: authenticate all matching vhosts for HTTP01
Previously, the nginx authenticator would set up the HTTP-01 challenge
response on a single HTTP vhost which matched the challenge domain.
The nginx authenticator will now set the challenge response on every
vhost which matches the challenge domain, including duplicates and HTTPS
vhosts.
This makes the authenticator usable behind a CDN where all origin
traffic is performed over HTTPS and also makes the authenticator work
more reliably against "invalid" nginx configurations, such as those
where there are duplicate vhosts.
* some typos
* dont authenticate the same vhost twice
One vhost may appear in both the HTTP and HTTPS vhost lists. Use a set()
to avoid trying to mod the same vhost twice.
* fix type annotations
* rewrite changelog entry
