Implements #7064

This change includes:

- An analyzer and codefix for enforcing naming styles and fixing symbol names to comply with a chosen & configurable set of naming rules.
- A set of Enforcement Levels that can be applied to different naming rules.
- A mechanism for linking from a lightbulb preview to the option that caused the related diagnostic to be created (could be moved to a different PR or release)
- Moving of the "Formatting" options pages under the Code Style node.