Versioned.versioned vs Versioned.versionedstaged is confusing

[tractorcow]

The distinction isn't clear and people often misuse these.

I suggest instead to split out version history into a new History extension that does just writing version history (which is what Versioned.versioned does).

Versioned extension can extend this, since it extends History view with staging.

Alternatively, they could be separate extensions, so you could even using staging without version history. We could rename Versioned to Staged instead in 5.0.