CHANGELOG.md in spandx-0.13.0 vs CHANGELOG.md in spandx-0.13.1

@@ -1,14 +1,18 @@
-Version 0.13.0
+Version 0.13.1
 
 # 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/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+
+## [0.13.1] - 2020-05-16
+### Fixed
+- Add `ext/**/*.c` and `ext/**/*.h` to list of files.
 
 ## [0.13.0] - 2020-05-12
 ### Added
 - Add progress bar
 - Add SPDX expression parser.