The main.c code is responsible for initialization and shutdown;
the mainloop.c code is responsible for running the main loop of Tor.
Splitting the "generic event loop" part of mainloop.c from the
event-loop-specific part is not done as part of this patch.
In dirauth:
* bwauth.c reads and uses bandwidth files
* guardfraction.c reads and uses the guardfraction file
* reachability.c tests relay reachability
* recommend_pkg.c handles the recommended-packages lines.
* recv_descs.c handles fingerprint files and processing incoming
routerinfos that relays upload to us
* voteflag.c computes flag thresholds and sets those thresholds on
routerstatuses when computing votes
In control:
* fmt_serverstatus.c generates the ancient "v1 server status"
format that controllers expect.
In nodelist:
* routerstatus_fmt.c formats routerstatus entries for a consensus,
a vote, or for the controller.
