Add status code label to handled_latency_seconds histogram

Hello!
I'd like to add status code label to the handled_latency_seconds histogram, to distinguish timings by this criteria.
To activate this feature, a boolean flag could be added to Configuration.
Looks like pretty obvious enhancement, but may be you see some drawbacks? What do you think?

If this is good idea, could you also please tell, how much time is required to publish a new release (after potential commit)?
Thanks!