pgsql: doc: mention psql -l uses the 'postgres' database by default

doc: mention psql -l uses the 'postgres' database by default

Reported-by: Mark Wood

Bug: 14912

Discussion: /messages/by-id/20171116171735.1474.30450@wrigleys.postgresql.org

Author: David G. Johnston

Backpatch-through: 10

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e0a0deca389849383ff6337a488300eb22f31cef

Modified Files
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doc/src/sgml/ref/psql-ref.sgml | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)