Expose `impl_static_sorter` macro?

[overlookmotel]

Would you consider exposing the impl_static_sorter macro?

With const_trait_impl feature, it's possible to create a const impl of PartialOrd for a user-defined type. It would then be possible use staticsort to sort this type.

This would work:

#![feature(const_trait_impl)]

use std::cmp::Ordering;
use staticsort::{staticsort, impl_static_sorter};

#[derive(Copy, Clone, Debug, PartialEq)]
struct Foo {
    inner: u32,
}

impl const PartialOrd for Foo {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        Some(if self.inner < other.inner {
            Ordering::Less
        } else if self.inner > other.inner {
            Ordering::Greater
        } else {
            Ordering::Equal
        })
    }
}

impl_static_sorter!(Foo);

const FOOS: [Foo; 3] = [Foo { inner: 3 }, Foo { inner: 2 }, Foo { inner: 1 }];
const FOOS_SORTED: [Foo; 3] = staticsort!(Foo, 0, 2, FOOS);

If you'd be open to this, I'd be happy to make a PR.