[noise] Announcing Noise.NET

[Nemanja Mijailovic]

Hi all!

I'm happy to announce the .NET Standard 2.0 implementation of the Noise
protocol framework. It's cross-platform (.NET Core 2.0 runs on Linux,
Mac OS, and Windows), libsodium-based library. Cryptographic primitives
it currently supports are:

- AESGCM and ChaChaPoly ciphers
- Curve25519 Diffie-Hellman function
- SHA256, SHA512, and BLAKE2b hash functions

It also supports multiple pre-shared symmetric keys, and all known one-way
and interactive handshake patterns from the specification. It's tested
against cacophony.txt and snow-multipsk.txt test vectors (Curve448 and BLAKE2s
excluded).

You can find the source code and examples here:
https://github.com/Metalnem/noise

The downloadable package is here:
https://www.nuget.org/packages/Noise.NET/

Coming soon:

- API documentation webpage
- BLAKE2s hash function
- Fallback protocols
- NoiseSocket and NLS
- Curve448 (probably)

Code reviews and API suggestions are welcome.

Nemanja