tor/src/tools/tor-fw-helper

We no longer recommend the use of this tool. Instead, please use the
pure-Go version of tor-fw-helper available at
https://gitweb.torproject.org/tor-fw-helper.git

Why?

The C code here was fine, but frankly: we don't trust the underlying
libraries. They don't seem to have been written with network security
in mind, and we have very little faith in their safety.