Reference commit for designating v0.4.1

This version was not tagged before, and it appears that the actual commit from which
the version was uploaded to pypi was not pushed to the repo.

As far as logbook's package contents, this version is identical to the one released.
Merge branch 'v0.4.1'
Bump version in setup.py to prevent conflict with 0.4.1
Test dependencies: On Python 2.5, require Jinja 2.6
Update CHANGES
Update CHANGES
Code cleanups
Check for PY2 instead of PY3
Remove six as a dependency
v0.4.2
Updated changelog
Master is 0.5-dev
Remove mail notifications, activate IRC notifications
Reenable email notifications (only for @vmalloc for now)
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Fix logging of unicode strings to streams in Python 2

When writing a unicode string to a file in Python 2, the string needs to be encoded before writing. This was handled properly in Logbook 0.4.1, but a bug was introduced in 0.4.2 which prevented this encoding from working properly.

The resulting problem can be reproduced easily by running this simple script with Logbook 0.4.2 on Python 2:

    import logbook

    log_handler = logbook.FileHandler('foo.log')
    log_handler.push_application()
    log = logbook.Logger('Foo')
    str = u'\u0431'
    log.info(str)

It results in this error within format_and_encode:

    UnicodeEncodeError: 'ascii' codec can't encode character u'\u0431' in position 30: ordinal not in range(128)

This commit restores the correct Logbook 0.4.1 behavior for Python 2.
Add test for outputting unicode strings to files
Merge branch 'master' of https://github.com/quantopian/logbook
Drop Python 2.5/3.2 support in tox and travis
Fix broken tests