bzr-email fails if committer has non-ascii gecos

[Glenn Morris]

Looking at _auto_user_id in config.py, which is what prints "cannot
decode passwd entry"), it already defaults to utf-8, only trying
get_user_encoding if utf-8 fails.

It seems like the lack of the locale package is indeed the problem.
A minimal example that shows the issue is:

  #!/usr/bin/python
  # -*- coding: utf-8 -*-
  string = 'Belaïche'
  print string.decode('utf-8')

(if my mail client mangled that, there is supposed to be a "LATIN SMALL
LETTER I WITH DIAERESIS" in string).

That works fine on my laptop, but if I uninstall the locales package, it
starts to fail with the same error as it does on Savannah:

  UnicodeEncodeError: 'ascii' codec can't encode character u'\xef' in
  position 4: ordinal not in range(128)

So I guess I should install locales...