Change the default ACME server to the v2 endpoint

[ohemorange]

Step 4 of #5365

• tools/deactivate.py
• acme/examples/example_client.py
  The backend data structures are the same for the different endpoints, but we might want to either determine the client to use based on the server like we do in certbot, or at least use acmev2 styles.

[bmw]

We won't be doing this in our 0.22.0 release which will be coming out before the endpoint goes live, so I'm kicking this to 0.23.0.

[shadycuz]

@bmw It's live, but I can't figure out how to change the endpoint?

Obtaining a new certificate
The currently selected ACME CA endpoint does not support issuing wildcard certificates.

[shadycuz]

Oh you need server flag --preferred-challenges dns-01 --server https://acme-v02.api.letsencrypt.org/directory

[kysil]

With command
certbot certonly --rsa-key-size 2048 --preferred-challenges dns-01 --server https://acme-v02.api.letsencrypt.org/directory

I have this answer:
Obtaining a new certificate Performing the following challenges: None of the preferred challenges are supported by the selected plugin

nginx 1.13.9
certbot 0.22.0
Centos 7.4

[shadycuz]

@kysil I used the instructions in this post #5719

[bmw]

Unfortunately we had to revert this change because things like certbot revoke --cert-path /path/to/cert would suddenly stop working due to a different account being used. #5820 should be resolved before releasing this change.

[bmw]

@ohemorange, are you able to get to this this week? If not, I can take it.

[ohemorange]

I've got it.