pgsql: Tighten up to_date/to_timestamp so that they are more likely to

Log Message:
-----------
Tighten up to_date/to_timestamp so that they are more likely to reject
erroneous input, rather than silently producing bizarre results as formerly
happened.

Brendan Jurd

Modified Files:
--------------
pgsql/doc/src/sgml:
func.sgml (r1.446 -> r1.447)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/func.sgml?r1=1.446&r2=1.447)
pgsql/src/backend/utils/adt:
formatting.c (r1.146 -> r1.147)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/formatting.c?r1=1.146&r2=1.147)
pgsql/src/test/regress/expected:
horology.out (r1.67 -> r1.68)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/horology.out?r1=1.67&r2=1.68)
timestamp.out (r1.37 -> r1.38)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/timestamp.out?r1=1.37&r2=1.38)
timestamptz.out (r1.31 -> r1.32)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/timestamptz.out?r1=1.31&r2=1.32)
pgsql/src/test/regress/sql:
horology.sql (r1.34 -> r1.35)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/sql/horology.sql?r1=1.34&r2=1.35)
timestamp.sql (r1.21 -> r1.22)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/sql/timestamp.sql?r1=1.21&r2=1.22)
timestamptz.sql (r1.18 -> r1.19)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/sql/timestamptz.sql?r1=1.18&r2=1.19)