Zheng Ping

Maybe https could be useful in an embedded system, hopefully someday https can be an optional feature of apple_pie.

I use the command: ``` openssl req -x509 -nodes -days 1825 -newkey rsa:4096 -keyout server.key -out server.crt ``` The generated self-signed certificates can be used in rustls. Pls check if...

@lucaswxp The private key contains `rsa` key and `pkcs8` key, and I added some codes to the `load_private_key` function, and rename it to `load_keys`: ``` fn load_keys(path: &Path) -> io::Result...