NEON support

Neon simd instructions for arm cpus are in nightly now I believe, someone could make a new branch and start implementing the simd trait for neon

I'm happy to help anyone get started, just ask for help and I'll walk you through it. You don't need a lot of specialist knowledge, it is a nice way to learn about simd.

It will be helpful to have an arm/neon capable cpu so you can test, though it isn't necessary.

该提问来源于开源项目：jackmott/simdeez