Compatibility breaks
* Remove module `rest_framework.v2`
* Refactor (optimize) `unittest.FilterByTagsMixin`
Minor compatibility breaks
* Rename module `exception` to `exceptions`
* Rename module `rest_framework.v3` to `rest_framework`
* Rename some attributes of `multimedia.ffmpeg` classes
Features
* Add many modules:
* `atlassian`
* `itertools`
* `module` (yes!)
* `selenium`
* `signals`
* `states`
* `string`
* `voluptuous`
* Add class `argparse.Range`
* Add function `argparse.multiple`
* Add function `collections.{merge_dicts, swap_dict_of_values}`
* Add decorator `decorators.run_once`
* Add modules and mixins in `django\*` module
* Add value `encoding.binary_type`
* Add function `humanize.naturalfrequency`
* Add function `types.isiterable`
* Add classes `types.{DummyObject,MissingType}`
* Add object `types.Missing instance of MissingType`
* Add mixins `unittest.{InMixin,InspectMixin}`
* Add class `unittest.Asserts`
* Add object `unittest.asserts`
Fixes and enhancements
* Countless fixes and enhancements
* Follow `os.path` import best practices
* Make `multimedia.ffmpeg` private functions public