remove .editorconfig

Bump version

Complete type annotations.

Bump version to rc.0

Release 1.0.0b12. Multiple changes:

* Rename `Base()` class into `Register()`.
* Rename `Render()` class into `RenderType()`.
* Implement `Style()` type: This changes the way how Sty's Register()
class sets, reads and renders styling rules. This allows for a more
Pythonic customization interface.
* Change yapf line-length to 88.

Documentation will be update with the next commits.

More info on Breaking Changes: #5 (comment)