[noise] Screech + WireGuard = Happy Noise Conversation

[Jason A. Donenfeld]

Hi Trevor,

Great news! After merging the pull request I submitted for screech
[1], and after fixing a few things on my side, I'm happy to report
that my implementation and your implementation interoperate!

In my first every foray into Rust, I've produced this little program
[2] that connects to a WireGuard server, does a handshake, and sends a
keepalive packet.

Things are off to a terrific start.

Jason

[1] https://github.com/trevp/screech/commit/5b7970cdde3b0188a410480ca0bef2cc147a78a3.patch
[2] https://paste.kde.org/pbrwyvrma/4i1h5h