Add CHANGELOG.md

Other changes:

* Rename the old `NEWS` file to `NEWS.OLD`.
* Update documentation links.

CHANGELOG.md

@@ -0,0 +1,25 @@
+# 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]
+
+### Added
+
+* This `CHANGELOG.md`. All notable changes to this project will be documented in
+  this file. The old `NEWS` file has been renamed to `NEWS.OLD` and is no longer
+  updated.
+
+### Changed
+
+* `SFC_SET_DITHER_ON_READ` and `SFC_SET_DITHER_ON_WRITE` enums comments in
+  public header (#677).
+
+### Fixed
+
+* Typo in `docs/index.md`.
+
+[Unreleased]: https://github.com/libsndfile/libsndfile/compare/1.0.31...HEAD

Makefile.am

@@ -13,7 +13,7 @@ endif
 endif
 
 EXTRA_DIST = libsndfile.spec.in sndfile.pc.in Scripts/android-configure.sh \
-	Scripts/linux-to-win-cross-configure.sh \
+	NEWS.OLD CHANGELOG.md Scripts/linux-to-win-cross-configure.sh \
 	CMakeLists.txt $(cmake_files) Win32
 
 cmake_files = cmake/ClipMode.cmake cmake/FindFLAC.cmake \

docs/_layouts/home.html

@@ -12,7 +12,7 @@ title: libsndfile home page
     <a href="#history">History</a> -+-
     <a href="#features">Features</a> -+-
     <a href="#similar-or-related-projects">Similar or related projects</a> -+-
-    <a href="https://github.com/libsndfile/libsndfile/blob/master/NEWS">News</a>
+    <a href="https://github.com/libsndfile/libsndfile/blob/master/CHANGELOG.md">News</a>
     <br>
     <a href="development.html">Development</a> -+-
     <a href="api.html">Programming interface</a> -+-