Add link reference definitions to CHANGELOG.md

The changelog of rustup already contained link labels, but did not contain matching link reference definitions. This commit adds matching link reference definitions for all previous releases. The link reference definitions point to the diff of two releases, except for the first release in the changelog, which points to the release tag.

Author: foresterre

CHANGELOG.md

@@ -1380,3 +1380,57 @@ Tad Hardesty
 - [Don't open /dev/tty if passed -y](https://github.com/rust-lang/rustup/pull/334).
 - [Add interactive install, `--default-toolchain` argument](https://github.com/rust-lang/rustup/pull/293).
 - [Rename rustup-setup to rustu-init](https://github.com/rust-lang/rustup/pull/303).
+
+
+[unreleased]: https://github.com/rust-lang/rustup/compare/v1.24.1...HEAD
+[1.24.1]: https://github.com/rust-lang/rustup/compare/1.24.0...1.24.1
+[1.24.0]: https://github.com/rust-lang/rustup/compare/1.23.1...1.24.0
+[1.23.1]: https://github.com/rust-lang/rustup/compare/1.23.0...1.23.1
+[1.23.0]: https://github.com/rust-lang/rustup/compare/1.22.1...1.23.0
+[1.22.1]: https://github.com/rust-lang/rustup/compare/1.22.0...1.22.1
+[1.22.0]: https://github.com/rust-lang/rustup/compare/1.21.1...1.22.0
+[1.21.1]: https://github.com/rust-lang/rustup/compare/1.21.0...1.21.1
+[1.21.0]: https://github.com/rust-lang/rustup/compare/1.20.2...1.21.0
+[1.20.2]: https://github.com/rust-lang/rustup/compare/1.20.1...1.20.2
+[1.20.1]: https://github.com/rust-lang/rustup/compare/1.20.0...1.20.1
+[1.20.0]: https://github.com/rust-lang/rustup/compare/1.19.0...1.20.0
+[1.19.0]: https://github.com/rust-lang/rustup/compare/1.18.3...1.19.0
+[1.18.3]: https://github.com/rust-lang/rustup/compare/1.18.2...1.18.3
+[1.18.2]: https://github.com/rust-lang/rustup/compare/1.18.1...1.18.2
+[1.18.1]: https://github.com/rust-lang/rustup/compare/1.18.0...1.18.1
+[1.18.0]: https://github.com/rust-lang/rustup/compare/1.17.0...1.18.0
+[1.17.0]: https://github.com/rust-lang/rustup/compare/1.16.0...1.17.0
+[1.16.0]: https://github.com/rust-lang/rustup/compare/1.15.0...1.16.0
+[1.15.0]: https://github.com/rust-lang/rustup/compare/1.14.0...1.15.0
+[1.14.0]: https://github.com/rust-lang/rustup/compare/1.13.0...1.14.0
+[1.13.0]: https://github.com/rust-lang/rustup/compare/1.12.0...1.13.0
+[1.12.0]: https://github.com/rust-lang/rustup/compare/1.11.0...1.12.0
+[1.11.0]: https://github.com/rust-lang/rustup/compare/1.10.0...1.11.0
+[1.10.0]: https://github.com/rust-lang/rustup/compare/1.9.0...1.10.0
+[1.9.0]: https://github.com/rust-lang/rustup/compare/1.8.0...1.9.0
+[1.8.0]: https://github.com/rust-lang/rustup/compare/1.7.0...1.8.0
+[1.7.0]: https://github.com/rust-lang/rustup/compare/1.6.0...1.7.0
+[1.6.0]: https://github.com/rust-lang/rustup/compare/1.5.0...1.6.0
+[1.5.0]: https://github.com/rust-lang/rustup/compare/1.4.0...1.5.0
+[1.4.0]: https://github.com/rust-lang/rustup/compare/1.3.0...1.4.0
+[1.3.0]: https://github.com/rust-lang/rustup/compare/1.2.0...1.3.0
+[1.2.0]: https://github.com/rust-lang/rustup/compare/1.1.0...1.2.0
+[1.1.0]: https://github.com/rust-lang/rustup/compare/1.0.0...1.1.0
+[1.0.0]: https://github.com/rust-lang/rustup/compare/0.7.0...1.0.0
+[0.7.0]: https://github.com/rust-lang/rustup/compare/0.6.5...0.7.0
+[0.6.5]: https://github.com/rust-lang/rustup/compare/0.6.4...0.6.5
+[0.6.4]: https://github.com/rust-lang/rustup/compare/0.6.3...0.6.4
+[0.6.3]: https://github.com/rust-lang/rustup/compare/0.6.2...0.6.3
+[0.6.2]: https://github.com/rust-lang/rustup/compare/0.6.1...0.6.2
+[0.6.1]: https://github.com/rust-lang/rustup/compare/0.6.0...0.6.1
+[0.6.0]: https://github.com/rust-lang/rustup/compare/0.5.0...0.6.0
+[0.5.0]: https://github.com/rust-lang/rustup/compare/0.4.0...0.5.0
+[0.4.0]: https://github.com/rust-lang/rustup/compare/0.3.0...0.4.0
+[0.3.0]: https://github.com/rust-lang/rustup/compare/0.2.0...0.3.0
+[0.2.0]: https://github.com/rust-lang/rustup/compare/0.1.12...0.2.0
+[0.1.12]: https://github.com/rust-lang/rustup/compare/0.1.11...0.1.12
+[0.1.11]: https://github.com/rust-lang/rustup/compare/0.1.10...0.1.11
+[0.1.10]: https://github.com/rust-lang/rustup/compare/0.1.9...0.1.10
+[0.1.9]: https://github.com/rust-lang/rustup/compare/0.1.8...0.1.9
+[0.1.8]: https://github.com/rust-lang/rustup/compare/0.1.7...0.1.8
+[0.1.7]: https://github.com/rust-lang/rustup/releases/0.1.7