Add unicode-capable IO to hooke.ui.commandline.

Add unicode-capable IO to hooke.ui.commandline.

The previous implementation produced:
  $ python bin/hooke -c 'flat_filter_playlist'
  ...
  hooke> Traceback (most recent call last):
  ...
  UnicodeEncodeError: 'ascii' codec can't encode character u'\xec'...

The new encoding detection functions in hooke.util.encoding came from
my libbe.util.encoding module for Bugs Everywhere.  From my original
BE commit (Tue 2008-11-25 15:47:19 -0500):

  get_encoding() is from Trac
    http://trac.edgewall.org/browser/trunk/trac/util/datefmt.py
    format_datetime()
  Trac has a BSD license
    http://trac.edgewall.org/wiki/TracLicense
  I don't know if such a small snippet requires us to "reproduce the
  above copyright" or where we need to reproduce it if it is needed.

  The stdout/stdin replacement code follows
    http://wiki.python.org/moin/ShellRedirectionFails

  References:
    http://wiki.python.org/moin/Unicode
    http://www.amk.ca/python/howto/unicode
    http://www.python.org/dev/peps/pep-0100/