openssl: add support for the Certificate Status Request TLS extension

Also known as "status_request" or OCSP stapling. This is defined in RFC6066
section 8.
gtls: add support for the Certificate Status Request TLS extension

Also known as "status_request" or OCSP stapling. This is defined in RFC6066
section 8, and requires GnuTLS 3.1.3 or higher.
curl: add --cert-status option

This enable the CURLOPT_SSL_VERIFYSTATUS functionality.