[noise] Go implementation

[Jonathan Rudenberg]

I pushed a mostly working pipe implementation to https://github.com/titanous/noise

The code needs more testing, comments/cleanup, and optimization, which I will do as I find the time. It also doesn’t support sending data in the handshake for simplicity of the initial implementation, I’ll be adding support for that in the future.

Next up: a SPKI implementation to use with Noise so that I can achieve transport security nirvana :)

Jonathan