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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REL9_4_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/721a8bb54602624b24d416f8d9b7b8f97701ecbd

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