* New exported API PyUnicode_Resize()

* The experimental Keep-Alive optimization was turned back
  on after some tweaks to the implementation. It should now
  work without causing core dumps... this has yet to tested
  though (switching it off is easy: see the unicodeobject.c
  file for details).

* Fixed a memory leak in the Unicode freelist cleanup code.

* Added tests to correctly process the return code from
  _PyUnicode_Resize().

* Fixed a bug in the 'ignore' error handling routines
  of some builtin codecs. Added test cases for these to
  test_unicode.py.