Allow library to be use in embedded projects.

[klangner]

This can be tested with:

cargo build --target thumbv6m-none-eabi 

Things to fix:
[ ] FFT crate doesn't support no_std. Maybe use https://gitlab.com/teskje/microfft-rs ?
[ ] Add libm for floats

[markubiak]

I think I touched on this a bit via email - is there much more to this than having a no-std core library?

[klangner]

Yes we did talk about it.
Regarding the issue, I'm not sure what is needed. Not sure if all libraries will work, e.g. FFT. I think this require some more research.