Convertdate

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* Better Python 2/3 compatibility
* Improve tests
* bump pytz requirement

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* Executing holidays module returns class with current year, not '2014'.
* Expand tests for French Republican, Bahai, Persian, holidays
* Add Travis CI testing

Bug fixes:

* Fix edge case when detecting the day of fall equinox in French Republican calendar
* Fix minor methods of calculating French Republican leap years.
* Change holidays.holidays.fathers_day from a method to a property
* Add pulaski_day to holidays.holidays
* Add pytz is dependency list

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* Fix Yom Kippur error in holidays.py (issue 3)

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* Typo in name of holidays.independence_day method
* Fix major bug in ordinal.from_gregorian
* Expand and organized tests

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Features:

* Add `ordinal` module, for counting the day of year
* Added Mexican national holidays
* Add `monthcalendar` functions

Other changes:

* Simplified logic in `ISO` module

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Features:

- Add list of day names and `day_name` function to French Republican converter
- Add multiple conversion methods to the French Republican calendar
- Add Dublin day count and Julian day count converters
- Add month names to Bahai and Hebrew calendars.

Other changes:

- Clarify that weekdays run Monday=0 to Sunday=6 (2)
- Change Julian converter to use astronomical notation (0 = 1 BCE, -1 = 1 BCE)
- Expanded tests