pgsql: Correct stdin/stdout usage in COPY .. PROGRAM

Correct stdin/stdout usage in COPY .. PROGRAM

The COPY documentation incorrectly stated, for the PROGRAM case,
that we read from stdin and wrote to stdout.  Fix that, and improve
consistency by referring to the 'PostgreSQL' user instead of the
'postgres' user, as is done in the rest of the COPY documentation.

Pointed out by Peter van Dijk.

Back-patch to 9.3 where COPY .. PROGRAM was introduced.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/8492d86342915cb466eeb2d896d9b49887f59350

Modified Files
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doc/src/sgml/ref/copy.sgml |   14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)