Rename Metrics/Torflow and Metrics/pytorctl to Core Tor/*
I looked through the list of Trac subcomponents under Metrics/ the other day and wondered whether Metrics/Torflow and Metrics/pytorctl really belong there or rather under Core Tor/.
My idea here is that Metrics/* subcomponents all do something with Tor network data but that Core Tor/* subcomponents are for anything that keeps the Tor network running. If all Metrics/* subcomponents would disappear tonight, the Tor network would still be running, we'd just fly blind. But if Metrics/Torflow disappeared, the Tor network would suddenly be damaged a lot, because clients would again need to rely on relays to be honest, and we know how that doesn't work out. It just happens to do measurements in order to do its job.
Regarding Metrics/pytorctl, the main reason for moving that to Core Tor/* would be that nothing else in Metrics/* uses it but only Metrics/Torflow does. So if we move one we should move both.
I discussed this with the component owners, and neither of them objected to this change.
I'll rename components in a minute, right after creating this ticket to document this change.