Add pure rust implementation

[iverks]

Hey. In order to improve the beginner-friendliness of this library I think it would be cool to add a pure rust backend.

I have found two candidates blasoxide and libblas. For me blasoxide doesn't compile out of the box. The author seems to have tried to get his library used in ndarray and nalgebra, but didn't succeed, and has later stopped working on this.

The latter crate works fine for me. Although no changes have been made in 4 years it seems to be the better candidate. From what I can tell it is compatible with BLAS, except for using generics to distinguish between f64 and f32 instead of having two versions of each function

[jedbrown]

I think you'd be better off putting a BLAS wrapper around faer, which has excellent performance, support for double-double, and LAPACK-level functionality.

[iverks]

I hadn't heard about that library, but it looks very cool. It actually seems there is an active development related to this. Thank you for the heads up. If that effort leads anywhere then that will probably be the better solution since the library actually is maintained.