bug#9917: 24.0.90; Make `goto-line' consistent with the line number from the minibuffer

[Juri Linkov]

> For `goto-line':
>
> Let a negative prefix arg use line numbering wrt the restriction (region), and
> let a positive prefix arg use line numbering wrt the buffer (widened).
>
> Likewise for a number read at the prompt: negative for restriction numbering,
> positive for full-buffer numbering.

A negative line number usually means counting from the end of the buffer.