Обсуждение: pgsql: Doc: improve documentation about ts_headline() function.

Doc: improve documentation about ts_headline() function.

Now that I've had my nose in that code, I thought the docs about
it left something to be desired.

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/fac00400846b742a0b8c804b3e075b385d5c3668

Modified Files
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doc/src/sgml/textsearch.sgml | 104 ++++++++++++++++++++++++-------------------
1 file changed, 57 insertions(+), 47 deletions(-)