The :mod:`curses` character-cell window methods now accept a full character
cell -- a spacing character optionally followed by combining characters -- in
addition to a single integer or byte character.  Add the wide-character read
methods :meth:`curses.window.get_wstr` and :meth:`curses.window.in_wstr`, and
the functions :func:`curses.erasewchar`, :func:`curses.killwchar` and
:func:`curses.wunctrl`.  These features are only available when built against
the wide-character ncursesw library.
