pgsql: Remove obsolete example of CSV log file name from log_filename d

Remove obsolete example of CSV log file name from log_filename document.

7380b63 changed log_filename so that epoch was not appended to it
when no format specifier is given. But the example of CSV log file name
with epoch still left in log_filename document. This commit removes
such obsolete example.

This commit also documents the defaults of log_directory and
log_filename.

Backpatch to all supported versions.

Christoph Berg

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/865868043af0f23cd72d4450ca4410828b016cea

Modified Files
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doc/src/sgml/config.sgml |    4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)