Trace cell queue times in Tor to measure Tor application "congestion"
In order to do #12892 (moved), we need to be able to measure congestion in the kernel and congestion in Tor. For the kernel, we can use libkqtime: https://github.com/robgjansen/libkqtime
This ticket is to add the components needed to compute Tor congestion, as part of dgoulet's new instrumentation framework.