Merge pull request rust-lang#2411 from rossmacarthur/ft/update-toml-link

Update TOML link to official website

src/ch01-03-hello-cargo.md

@@ -72,10 +72,8 @@ edition = "2018"
 <span class="caption">Listing 1-2: Contents of *Cargo.toml* generated by `cargo
 new`</span>
 
-This file is in the [*TOML*][toml]<!-- ignore --> (*Tom’s Obvious, Minimal
-Language*) format, which is Cargo’s configuration format.
-
-[toml]: https://github.com/toml-lang/toml
+This file is in the [*TOML*](https://toml.io)<!-- ignore --> (*Tom’s Obvious,
+Minimal Language*) format, which is Cargo’s configuration format.
 
 The first line, `[package]`, is a section heading that indicates that the
 following statements are configuring a package. As we add more information to