Correct terminology in Clone

[GKFX]

I think the current wording around Clone here is confusing:

• "Rust does not allow you to reimplement Copy" - reimplement isn't a piece of Rust terminology, but as written it sounds like you can't write impl Copy for X, which you can.
• "you may reimplement Clone" - again reimplement isn't really a thing that you do to a trait, the distinction is between manually implementing and deriving.
• "you can automatically make anything Copy be Clone as well" - you don't have a choice about it, so it doesn't really make sense to say you "can ... make" this happen.

[rustbot]

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