fix readme links

Author: alecmocatta

README.md

@@ -29,10 +29,16 @@ println!("{:#?}", plus_one);
 ```
 
 This library aims to work in as simple and safe a way as possible. On stable
-Rust the returned closures implement [`traits::FnOnce`], [`traits::FnMut`] and
-[`traits::Fn`], and on nightly Rust [`std::ops::FnOnce`], [`std::ops::FnMut`]
-and [`std::ops::Fn`] are implemented as well using the `unboxed_closures` and
-`fn_traits` features (rust issue [#29625](https://github.com/rust-lang/rust/issues/29625)).
+Rust the wrapped closures implement
+[`traits::FnOnce`](https://docs.rs/serde_closure/0.3/serde_closure/traits/trait.FnOnce.html),
+[`traits::FnMut`](https://docs.rs/serde_closure/0.3/serde_closure/traits/trait.FnMut.html)
+and [`traits::Fn`](https://docs.rs/serde_closure/0.3/serde_closure/traits/trait.Fn.html),
+and when the "nightly" feature is passed
+[`std::ops::FnOnce`](https://doc.rust-lang.org/std/ops/trait.FnOnce.html),
+[`std::ops::FnMut`](https://doc.rust-lang.org/std/ops/trait.FnMut.html) and
+[`std::ops::Fn`](https://doc.rust-lang.org/std/ops/trait.Fn.html) are
+implemented as well using the `unboxed_closures` and `fn_traits` features (rust
+issue [#29625](https://github.com/rust-lang/rust/issues/29625)).
 
  * There are three macros,
    [`FnOnce`](https://docs.rs/serde_closure/0.3/serde_closure/macro.FnOnce.html),

src/lib.rs

@@ -25,11 +25,11 @@
 //! ```
 //!
 //! This library aims to work in as simple and safe a way as possible. On stable
-//! Rust the returned closures implement [`traits::FnOnce`], [`traits::FnMut`]
-//! and [`traits::Fn`], and on nightly Rust [`std::ops::FnOnce`],
-//! [`std::ops::FnMut`] and [`std::ops::Fn`] are implemented as well using the
-//! `unboxed_closures` and `fn_traits` features (rust issue
-//! [#29625](https://github.com/rust-lang/rust/issues/29625)).
+//! Rust the wrapped closures implement [`traits::FnOnce`], [`traits::FnMut`]
+//! and [`traits::Fn`], and when the "nightly" feature is passed
+//! [`std::ops::FnOnce`], [`std::ops::FnMut`] and [`std::ops::Fn`] are
+//! implemented as well using the `unboxed_closures` and `fn_traits` features
+//! (rust issue [#29625](https://github.com/rust-lang/rust/issues/29625)).
 //!
 //!  * There are three macros, [`FnOnce`](macro@FnOnce), [`FnMut`](macro@FnMut)
 //!    and [`Fn`](macro@Fn), corresponding to the three types of Rust closure.