Fixed extra line when duplicating region

[Yevgnen]

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When duplicating region, I think there is an extra newline is include when the cursor is at bol.

This

will result in

This PR fixed this.

(I'm not sure whether this is indeed an issue. But following many other library or emacs built in functions, IIRC when the cursor is at bol, they generally don't count that line. I have to 'fix' that line every time I duplicate a region.)

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Thanks!

[failable]

bump ;)

[bbatsov]

Thanks!