* Add theming docs
* Update some components to the new class name structure
* Add docs about class name updates
* Update coding guidelines
* Minor improvements
* Update docs/theming/class-names-update-280.md
Co-authored-by: Darren Ethier <darren@roughsmootheng.in>
Co-authored-by: Darren Ethier <darren@roughsmootheng.in>