autotrace: delete (#13897)

Hasn't had an upstream release for well over a decade, we've already
been patching it to build properly for years, there are a ton of known
vulns out there & fresh ones are still being discovered, and Debian
have just murdered it for the above reasons. Time to die.

Refs:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=863210
https://blogs.gentoo.org/ago/2017/05/20/autotrace-multiple-vulnerabilities-the-autotrace-nightmare/