Issue #13930: Adds ability for 2to3 to write its output to a different
directory tree instead of overwriting the input files.  Adds three command
line options: -o/--output-dir, -W/--write-unchanged-files and --add-suffix.

Feature backports into stable release branches for 2to3 are allowed by
a special exemption:
 http://mail.python.org/pipermail/python-dev/2011-December/115089.html
diff --git a/Misc/NEWS b/Misc/NEWS
index a00331d..583673c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -443,6 +443,11 @@
 Tools/Demos
 -----------
 
+- Issue #13930: 2to3 is now able to write its converted output files to another
+  directory tree as well as copying unchanged files and altering the file
+  suffix.  See its new -o, -W and --add-suffix options.  This makes it more
+  useful in many automated code translation workflows.
+
 - Issue #13628: python-gdb.py is now able to retrieve more frames in the Python
   traceback if Python is optimized.