pgsql: docs: clarify that today/tomorrow/yesterday is at 00:00

docs: clarify that today/tomorrow/yesterday is at 00:00

This should help people clearly know that these days start at midnight.

Reported-by: David Harper

Discussion: /messages/by-id/156258047907.1181.11324468080514061996@wrigleys.postgresql.org

Backpatch-through: 9.4

Branch
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REL9_5_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/315c7a8153f722cbdd62afd9ef68511a79d927d4

Modified Files
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doc/src/sgml/datatype.sgml | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)