Cmomy

Added

- Moved module `_docstrings_` to `docstrings`. This can be used by other
modules.

Changed

- Update package layout
- New linters via pre-commit
- Development env now handled by tox

- Now use `module-utilities` to handle caching and docfiller.

[`v0.3.0...v0.4.0`](https://github.com/usnistgov/cmomy/compare/v0.3.0...v0.4.0)

Full set of changes:
[`v0.2.2...v0.3.0`](https://github.com/usnistgov/cmomy/compare/v0.2.2...v0.3.0)

Full set of changes:
[`v0.2.1...v0.2.2`](https://github.com/usnistgov/cmomy/compare/v0.2.1...v0.2.2)

Full set of changes:
[`v0.2.0...v0.2.1`](https://github.com/usnistgov/cmomy/compare/v0.2.0...v0.2.1)

Full set of changes:
[`v0.1.9...v0.2.0`](https://github.com/usnistgov/cmomy/compare/v0.1.9...v0.2.0)

Full set of changes:
[`v0.1.8...v0.1.9`](https://github.com/usnistgov/cmomy/compare/v0.1.8...v0.1.9)