Using the mold linker for fun and 3x-8x link time speedups

I heard a lot of good things about mold and finally dove in after hitting some crippling compile times on a big rust project.

It barely made a difference, which was disappointing. Pretty much forgot about it after that but randomly tried it on a whim on a smaller project and the speedup was huge. After some rough testing going through most of my repo's it's very hit and miss with improvements but never was slower.

It's the only linker I use now. Not sure about C++ stuff but do investigate further if you aren't initially impressed, I've joined the fanclub.