issue 130 stabilization guide

Author: Rajkumar Natarajan

src/stabilization_guide.md

@@ -12,7 +12,7 @@ following steps.
 ## Documentation PRs
 
 If any documentation for this feature exists, it should be
-in the `Unstable Book`, located at `src/doc/unstable-book`.
+in the [`Unstable Book`], located at [`src/doc/unstable-book`].
 If it exists, the page for the feature gate should be removed.
 
 If there was documentation there, integrating it into the
@@ -177,3 +177,5 @@ if something { /* XXX */ }
 [The Reference]: https://github.com/rust-lang-nursery/reference
 [The Book]: https://github.com/rust-lang/book
 [Rust by Example]: https://github.com/rust-lang/rust-by-example
+[`Unstable Book`]: https://doc.rust-lang.org/unstable-book/index.html
+[`src/doc/unstable-book`]: https://github.com/rust-lang/rust/tree/master/src/doc/unstable-book