Prepare changelog for 0.5.0 release (kowainik#153)

Prepare changelog for the 0.4.0 release [skip ci] (kowainik#119)

* Prepare changelog for the 0.4.0 release [skip ci]

* Improve docs and do some pretty things

Generate hlint rules

Improve README (kowainik#58)

* Improve README

* Minor improvements

[kowainik#44] Derive parsers from pretty-printers (kowainik#45)

* [kowainik#44] Derive parsers from pretty-printers

* Fix after review

* Fix after second review, and update CHANGLOG

[kowainik#5] Improve documentation (kowainik#42)

* [kowainik#5] Improve documentation

* Update README.md

* Add cabal description