-# Second argument: either "set" or "get" or "put"
-#
-# "set" install certbot on remote server and requests a new certificate
-# for it. This needs two more arguments: an e-mail address for future
-# communication with LetsEncrypt, and the domain for which to request
-# the certificate (might plausibly be equivalent to the first argument
-# though). This needs port 80 open on the server.