Introduces a new command line switch `--must-staple` to `run` and `renew`.
Using this switch will add the must staple TLS extension to the CSR generated by lego and thus also to the generated certificate.
This does not work with user specified CSRs!
Fixes#270
client.RenewCertificate now supports CSRs, and in fact prefers them,
when renewing certificates. In other words, if the certificate was
created via a CSR then using that will be attempted before re-generating
off a new private key.
Also adjusted the API of ObtainCertificateForCSR to be a little
more in line with the original ObtainCertificate function.
This commit also breaks requestCertificate() into two parts, the first of
which generates a CSR, the second of which became requestCertificateForCsr()
which does what the name implies.
Add 2 new functions to acme.Client for registration stuff:
* QueryRegistration: This performs a POST on the client
registration's URI and gets the updated registration info.
* DeleteRegistration: This deletes the registration as currently
configured in the client.
The latter, while a part of the IETF draft, may not be 100%
functional in LE yet, my tests showed that resources were still
available after deletion.
* new ChallengeProvider with Present and CleanUp methods
* new Challenge type describing `http-01`, `tls-sni-01`, `dns-01`
* new client.SetChallengeProvider to support custom implementations
Also removes revokation abilities from RenewCertificate.
Makes the API more orthogonal. These things are not provided by the
ACME protocol, but were convenience helpers.
Last paragraph of ACME spec, section 6.5:
To check on the status of an authorization, the client sends a GET
request to the authorization URI, and the server responds with the
current authorization object. In responding to poll requests while
the validation is still in progress, the server MUST return a 202
(Accepted) response with a Retry-After header field.
