Paul Sokolovsky 4475f32420 tools/tinytest-codegen: Ignore system locale, write output in UTF-8.
Way to reproduce a UnicodeEncodeError without this patch:

    LC_ALL=C tinytest-codegen.py ...
2017-12-15 12:04:10 +02:00
..
2017-05-29 11:36:05 +03:00
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