Added a CHANGELOG. Fixed #2.

Author: green-coder

CHANGELOG

@@ -0,0 +1,31 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+
+Versions prior to v0.1.0 are considered experimental, their API may change.
+
+## [Unreleased]
+
+### Added
+- this changelog file.
+
+## [0.0.3] - 2020-07-26
+
+### Added
+- the setup for a nice cljdoc documentation.
+
+## [0.0.2] - 2020-07-26
+
+### Added
+- the generator function in a separate namespace.
+- a documentation in `doc/`.
+
+### Changed
+- some functions in the helpers.
+
+## [0.0.1] - 2020-05-13
+
+### Added
+- the `valid?` function, to validate data against a model.
+- the helper functions, to build the models.

doc/cljdoc.edn

@@ -1,4 +1,6 @@
-{:cljdoc.doc/tree [["Introduction"      {:file "doc/README.md"}]
+{:cljdoc.doc/tree [["Readme"            {:file "README.md"}]
+                   ["Changes"           {:file "CHANGELOG.md"}]
+                   ["Introduction"      {:file "doc/introduction.md"}]
                    ["Design Choices"    {:file "doc/design_choices.md"}]
                    ["Model Anatomy"     {:file "doc/model_anatomy.md"}]
                    ["Model Builder"     {:file "doc/model_builder.md"}]