Feature request: some way to know which termination signal was received

[BatmanAoD]

I see that the crate defines SignalType, but it doesn't appear to have any way for the registered signal handler to know which signal it received, or a way to register different handlers for different signals.

Could something like that be added? Even something as simple as using tracing to instrument the span in which the callback is invoked with an attribute corresponding to the signal would be helpful for logging.