Turn the GroupKey into a string that is composed of the matchers if the
path in the routing tree and the grouping labels.
Only hash it at the very end to ensure we don't exceed size limits of
integration APIs.
This adds a new nflog package meant to replace provider.Notifies. It
has a central protobuf type package, which is also meant for usage for
other packages and the API.
The generated Go types are also the in-memory representation.
Fabian Reinartz