Added

• Added better typing and PEP-561 compliance (#320).
• Added the is_anniversary() method as an alias of is_birthday() (#298).

Changed

• Dropped support for Python 3.4.
• is_utc() will now return True for any datetime with an offset of 0, similar to the behavior in the 1.* versions (#295)
• Duration.in_words() will now return 0 milliseconds for empty durations.

Fixed

• Fixed various issues with timezone transitions for some edge cases (#321, (#350)).
• Fixed out of bound detection for nth_of("month") (#357).
• Fixed an error where extra text was accepted in from_format() (#372).
• Fixed a recursion error when adding time to a DateTime with a fixed timezone (#431).
• Fixed errors where Period instances were not properly compared to other classes, especially timedelta instances (#427).
• Fixed deprecation warnings due to internal regexps (#427).
• Fixed an error where the test() helper would not unset the test instance when an exception was raised (#445).
• Fixed an error where the week_of_month attribute was not returning the correct value (#446).
• Fixed an error in the way the Z ISO-8601 UTC designator was not parsed as UTC (#448).

Locales

• Added the nl locale.
• Added the it locale.
• Added the id locale.
• Added the nb locale.
• Added the nn locale.