Separation of guide into 2 parts

[zubtsov]

There are two aspects to this guide:

1. Rules and guidelines that can be automatically checked by a Scala linter, checker, or validator.
2. Rules that can't be enforced automatically.

For this guide, it makes sense to provide the first part in the form of a configuration that can be automatically applied and enforced by Scala formatting tools. This way, adopters of this guide don't have to remember or create their own configuration. Instead, they can simply follow a single entry in the guide: "use this formatting configuration."

This guide can then focus on more complex aspects of good and clean code.