Log Message:
py-arrow: updated to 0.15.6

0.15.6:

- [NEW] Added support for parsing and formatting `ISO 8601 week dates \ 
<https://en.wikipedia.org/wiki/ISO_week_date>`_ via a new token ``W``, for \ 
example:

.. code-block:: python

    >>> arrow.get("2013-W29-6", "W")
    <Arrow [2013-07-20T00:00:00+00:00]>
    >>> utc=arrow.utcnow()
    >>> utc
    <Arrow [2020-01-23T18:37:55.417624+00:00]>
    >>> utc.format("W")
    '2020-W04-4'

- [NEW] Formatting with ``x`` token (microseconds) is now possible, for example:

.. code-block:: python

    >>> dt = arrow.utcnow()
    >>> dt.format("x")
    '1585669870688329'
    >>> dt.format("X")
    '1585669870'

- [NEW] Added ``humanize`` week granularity translation for German, Italian, \ 
Polish & Taiwanese locales.
- [FIX] Consolidated and simplified German locales.
- [INTERNAL] Moved testing suite from nosetest/Chai to pytest/pytest-mock.
- [INTERNAL] Converted xunit-style setup and teardown functions in tests to \ 
pytest fixtures.
- [INTERNAL] Setup Github Actions for CI alongside Travis.
- [INTERNAL] Help support Arrow's future development by donating to the project \ 
on `Open Collective <https://opencollective.com/arrow>`_.