changelog entry for #4666

[skip ci]

Author: hvr

Cabal/changelog

@@ -2,6 +2,11 @@
 
 2.2.0.0 (current development version)
 	* Remove unused '--allow-newer'/'--allow-older' support (#4527)
+	* Change `rawSystemStdInOut` to use proper type to represent
+	  binary and textual data; new 'Distribution.Utils.IOData' module;
+	  removed obsolete 'startsWithBOM', 'fileHasBOM', 'fromUTF8',
+	  and 'toUTF8' functions; add new `toUTF8BS`/`toUTF8LBS`
+	  encoding functions. (#4666)
 	* Warn about `.cabal` file-name not matching package name
 	  in 'cabal check' (#4592)
 	* By default 'ar' program receives arguments via '@file' format.