BREAKING CHANGE: Change the `--force/--no-force` cli option to
`--duplicates/--no-duplicates` since it describes a little clearer what
using it actually achieves (adding quote duplicates or not to output).
This allows headers to be created by a formatter, which will
*only* be added to the very first entry created and not to
each entry. Currently for example this is used to create
a csv header but not for each document in turn.