Certbot ECDSA support

Certbot, part of EFF’s larger effort to encrypt the entire Internet, is a free, open source software tool used to encrypt traffic to tens of millions of websites. By automatically generating and configuring Let’s Encrypt certificates on webservers to enable HTTPS, Certbot improves the privacy and security of hundreds of millions of users worldwide. The project strives to provide the highest standard of security, which is why we are keen to implement Elliptic Curve Digital Signature Algorithm (ECDSA) support. ECDSA support in Certbot will improve privacy, performance, and trust for Internet users via improved authentication and security.