Flake8-spellcheck

------
* Add more words to python dictionary
* Add initial support for optional in-built dictionaries (e.g. Django)

------
* Handle special cases when spellchecking words ending with 's

-----
* Add `hasattr` to in-built python dictionary

-----
* Introduce Changelog
* Correctly detect fully UPPERCASE variables (thanks gera)
* Correctly detect methods and variables with leading underscores (thanks gera)
* Added new inbuilt words to python dictionary