Create os.fsdecode(): decode from the filesystem encoding with surrogateescape
error handler, or strict error handler on Windows.

 * Rewrite os.fsencode() documentation
 * Improve os.fsencode and os.fsdecode() tests using the new PYTHONFSENCODING
   environment variable
diff --git a/Misc/NEWS b/Misc/NEWS
index 23245a8..31fec7a 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -116,6 +116,9 @@
 Library
 -------
 
+- Create os.fsdecode(): decode from the filesystem encoding with
+  surrogateescape error handler, or strict error handler on Windows.
+
 - Issue #3488: Provide convenient shorthand functions ``gzip.compress``
   and ``gzip.decompress``.  Original patch by Anand B. Pillai.