Adding support for basic authentification

[p3l1]

I am planning to use the acme-dns service behind an nginx reverse proxy with basic authentification, so the api is not exposed on the internet directly.

Because there will be many clients using the api, switching the /register endpoint on and off is not a sufficient solution for my usecase.

Would you accept a PR for this feature?

[mbag]

Hi @p3l1 , yes I/we will accept the PR for this feature.

[ZPascal]

@p3l1 Good idea. After the implementation of the new feature, I can remove my custom validation script, the --manual-auth-hook call inside certbot certonly --manual-public-ip-logging-ok --manual --manual-auth-hook /srv/test/acme-dns-client.py --preferred-challenges=dns --email webmaster@test.com --server https://acme-v02.api.letsencrypt.org/directory --agree-tos -d ...... command and directly using the plugin.