pgsql: Adjust various references to GEQO being non-deterministic.

Adjust various references to GEQO being non-deterministic.

It's still non-deterministic in some sense ... but given fixed settings
and identical planning problems, it will now always choose the same plan,
so we probably shouldn't tar it with that brush.  Per bug #6565 from
Guillaume Cottenceau.  Back-patch to 9.0 where the behavior was fixed.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/c94b43ce39f3ee48db04fb8284de0db12526af92

Modified Files
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doc/src/sgml/config.sgml |   17 +++++++++--------
1 files changed, 9 insertions(+), 8 deletions(-)