Linker for Clang

Followup: it's now 2016, and llvm has made some steady progress on their own linker. It's called "lld", and the website is here. It works fine to create i386 and x86_64 binaries, while work is ongoing to target other systems.

This should remove the dependency on GNU tools for BSDs, once it is considered stable enough.

I was running 'clang' instead of 'clang++', meaning it didn't link the C++ standard library.