Rename one of the two sendme.h files
We have a convention that, to avoid confusion, two directories should never have headers with the same name. Our rectify_include_paths.py
tool takes advantage of this fact to find a canonical path for each header. But in 0.4.1, we now have two conflicting headers:
./src/core/or/sendme.h
./src/trunnel/sendme.h
Let's rename one of these.