CHANGELOG: add notes for 0.5.8 and 0.6.3

Author: zombiezen

CHANGELOG.md

@@ -4,7 +4,29 @@ The format is based on [Keep a Changelog][], and this project adheres to
 [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 [Keep a Changelog]: https://keepachangelog.com/en/1.0.0/
-[Unreleased]: https://github.com/yourbase/yb/compare/v0.6.2...HEAD
+[Unreleased]: https://github.com/yourbase/yb/compare/v0.6.3...HEAD
+
+## [0.6.3][] - 2021-03-08
+
+Version 0.6.3 changes the build environment keychain name.
+
+[0.6.3]: https://github.com/yourbase/yb/releases/tag/v0.6.3
+
+### Changed
+
+-  On macOS, the empty, default keychain that yb creates will now be called
+   `login` instead of `yb` for compatibility with more programs.
+
+## [0.5.8][] - 2021-03-08
+
+Version 0.5.8 backports a change to the build environment keychain name.
+
+[0.5.8]: https://github.com/yourbase/yb/releases/tag/v0.5.8
+
+### Changed
+
+-  On macOS, the empty, default keychain that yb creates will now be called
+   `login` instead of `yb` for compatibility with more programs.
 
 ## [0.6.2][] - 2021-03-01