Croniter

-------------------

- credits
- history stripping (security)
- Handle -Sun notation, This fixes `119 <https://github.com/taichino/croniter/issues/119>`_.
[kiorky]
- Handle invalid ranges correctly, This fixes `114 <https://github.com/taichino/croniter/issues/114>`_.
[kiorky]

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- Pypi hygiene
[hugovk]

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- fix `107 <https://github.com/taichino/croniter/issues/107>`_: microsecond threshold
[kiorky]

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- fix ``get_next`` while preserving the fix of ``get_prev`` in 7661c2aaa
[Avikam Agur <avikampagaya-inv.com>]

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- Don't count previous minute if now is dynamic
If the code is triggered from 5-asterisk based cron
``get_prev`` based on ``datetime.now()`` is expected to return
current cron iteration and not previous execution.
[Igor Khrol <igor.khroltoptal.com>]

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- More DST fixes
[Kevin Rose <kbrosegithub>]