In order to provide richer telemetry, it would be useful to provide the raw histogram bins found in the internal Circonus histograms to the outside world.

I have added data members to histogram_impl to record these bins so they can be made available via gRPC. However, it seems the gRPC messages from MetricsServiceSink are lifted directly from prometheus. This schema does not feature a message type that is appropriate for exposing these bins.

Would you have any guidance or preference on how this data should be exposed to the outside world?