This is way overdue.

Credit for the packaging work:
https://github.com/bqv/rc/blob/live/rc/packages/yggdrasil.scm

It did need some more work though. The Go importer leaves a few things
to be desired, but that's for another thread.

Anyways, I tested it and it works. System service could be restarted
after a reconfigure without any issues.

Please apply this soon, because nodes running the outdated versions
can't connect to ones running this new version, due to breaking
protocol changes.