Don't abort when backup files already exist. Don't allow alternative names. Rationale: - When the user wants to revert, he shouldn't be stopped from doing this just because some old backups will be overwritten. - To not clobber important files by accident, alternative names for backup files were disabled. As the backup target now has a fixed name, the user doesn't have to be informed about the backup copy (unless --verbose)

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port:4:export

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port:4:vaportight

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port:4:import/export

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FIXME: history is wrong here

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port:1:1:-:eggs:import

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port:1:2:+:eggs:vaportight

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port:1:3:+:eggs:import/export

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port:0:2:+:spam:export

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port:0:1:+:spam:import

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port:4:import/export