Tests fail in Python 3 with non UTF-8 locale

[Barry Warsaw]

$ LC_ALL='POSIX' python3 setup.py test

This fails the test_save_config_non_ascii test. This is important because I'm adding support to the Debian packaging for Python 3 and in an sbuild environment, the tests are run in the POSIX locale.

[Barry Warsaw (barry)]

======================================================================
ERROR: test_save_config_non_ascii (configglue.tests.test_parser.TestSchemaConfigParser)
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Traceback (most recent call last):
  File "/home/barry/projects/ubuntu/configglue/configglue-1.1.0/configglue/tests/test_parser.py", line 1005, in test_save_config_non_ascii
    self._check_save_file(expected)
  File "/home/barry/projects/ubuntu/configglue/configglue-1.1.0/configglue/tests/test_parser.py", line 1015, in _check_save_file
    self.parser.save(open(filename, 'w'))
  File "/home/barry/projects/ubuntu/configglue/configglue-1.1.0/configglue/parser.py", line 599, in save
    self.write(fp)
  File "/home/barry/projects/ubuntu/configglue/configglue-1.1.0/configglue/parser.py", line 584, in write
    fp.write("%s\n" % (key))
UnicodeEncodeError: 'ascii' codec can't encode character '\xf3' in position 7: ordinal not in range(128)