Dependency on std is too strong

[stephanemagnenat]

Currently, some features depend on std, such as the re-exporting of num_trait's Float (from here):

#[cfg(feature = "std")]
pub use num_traits::{Float, Pow};

However, num_trait has the ability to export these using libm even under no_std (from here):

#[cfg(any(feature = "std", feature = "libm"))]
pub trait Float: Num + Copy + NumCast + PartialOrd + Neg<Output = Self> {
...

I think that it would be good for ordered-float to do the same, enabling a wider use of its feature set under no_std.

Does the maintainer agree?

[stephanemagnenat]

Woah that was fast, thank you very much! :-)

[stephanemagnenat]

Fyi I document this addition in #165.