bug#81536: document sort does not have different input and output separators

[Dan Jacobson]

Fine.
By the way, as sort in control of both input and output separators,
why not allow the user to adjust them independently,
with --input-separator,  --output-separator.
You know that's not always as easy to do with a post processing filter,
be it tr(1), sed(1), perl(1), etc.