Update changelog for version 0.2.0

Author: tarleb

CHANGELOG.md

@@ -3,6 +3,13 @@
 `hslua-module-doclayout` uses [PVP Versioning][1].
 The changelog is available [on GitHub][2].
 
+## 0.2.0
+
+* Full test coverage of all provided Lua functions.
+* Use documented module, including all function docs in the
+  exported Haskell structure.
+* Test with all GHC 8 major versions.
+
 ## 0.1.0
 
 * Initial release.