More fine-grained modular decomposition
We should chop up our huger C files into smaller ones, based on actual module boundaries.
This will make it harder for us to merge pending branches that touch that code, but those are at a low ebb right now, so it's a good time.
The top 10 offenders in our current codebase are:
4614 src/or/rendservice.c
4839 src/or/channel.c
5200 src/or/connection.c
5386 src/or/or.h
5648 src/common/util.c
5666 src/or/directory.c
5688 src/or/routerparse.c
5771 src/or/routerlist.c
7223 src/or/control.c
8006 src/or/config.c
(updated May 2017)