An early version of the spec indicated that clients should process issuance
sequentially, following Link rel=next from an account URL to an authz URL, to a
new-cert URL. However, the spec has long since moved to putting these URLs in
the directory.
Certbot nominally supports either; This change consolidates on always using the
directory, simplifying things and making the transition to the latest ACME spec
easier.
* Ensure tests pass with openssl 1.1
A bunch of the acme.standalone and acme.crypto_util tests were using
weak crypto that is now prohibited :/
* lint
* lintlint
* Fix symlink