Roughenough 2.0 RFC-draft compliant cryptographic time sync

I've released version 2.0 of roughenough, a Rust implementation of the draft IETF Roughtime protocol (https://datatracker.ietf.org/doc/draft-ietf-ntp-roughtime/). The Roughtime protocol provides cryptographic secure time synchronization with detection of server malfeasance.

Release 2.0.x of roughenough is a rewrite of the implementation to be simpler, more comprehensive, and more performant. The repo has multiple crates that implement:

  * Performance-oriented async UDP server
  * Command-line client with multiple output formats
  * Multiple backends for secure key management for the server
  * Clients can (optionally) report malfeasance to a remote server for analysis