Caseless-dictionary

Made the following improvements:
- added py.typed file
- fixed few pylint errors
- added pylint, mypy, blue, and pylama checks to pipeline

What's Changed
* Typing changes by tybruno in https://github.com/tybruno/caseless-dictionary/pull/10


**Full Changelog**: https://github.com/tybruno/caseless-dictionary/compare/v2.0.0...v2.0.1

What's Changed
* Add caseless attr dict by tybruno in https://github.com/tybruno/caseless-dictionary/pull/9

- Added more caseless dictionaries.
- Added caseless attribute dictionaries.

**Full Changelog**: https://github.com/tybruno/caseless-dictionary/compare/v1.0.3...v2.0.0

- Updated the ModifiableItemsDictionary requirements
- Modified imports to use `import` instead of `from`
- Cleaned up `setup.py`

Updates
* Updated project description in `setup.py`.
* Gave acknowledgments to Raymond Hettinger rhettinger

Updates

Added Badges to `README.md`

Initial release of `CaselessDict`, `TitleCaselessDict`, `UpperCaselessDict`, and testing.