docs: add initial changelog and simplify readme

CHANGELOG.md

@@ -0,0 +1,14 @@
+# Change Log
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/)
+and this project adheres to [Semantic Versioning](http://semver.org/).
+
+<!-- next-header -->
+## [Unreleased] - ReleaseDate
+
+### Added
+- Initial version so no changes to report.
+
+<!-- next-url -->
+[Unreleased]: https://github.com/rust-cli/argfile/compare/e7b7555...HEAD

README.md

@@ -162,22 +162,7 @@ rustup = [
 ]
 ```
 
-## Commands
+# Credits
 
-Run `metapac -h` to see an overview of the commands available with
-`metapac`.
-
-## Naming
-
-`metapac` combines the words "package" and "define".
-
-## Backend Pitfalls
-
-### Pipx
-
-Some packages like
-[`mdformat-myst`](https://github.com/executablebooks/mdformat-myst) do
-not provide an executable themselves but rather act as a plugin to
-their dependency, which is mdformat in this case. Please install such
-packages explicitly by running: `pipx install <package-name>
---include-deps`.
+This project was forked from <https://github.com/steven-omaha/pacdef> so
+credits to the author(s) of that project for all their prior work.