pgsql: After a MINVALUE/MAXVALUE bound, allow only more of the same.

After a MINVALUE/MAXVALUE bound, allow only more of the same.

In the old syntax, which used UNBOUNDED, we had a similar restriction,
but commit d363d42bb9a4399a0207bd3b371c966e22e06bd3, which changed the
syntax, eliminated it. Put it back.

Patch by me, reviewed by Dean Rasheed.

Discussion: http://postgr.es/m/CA+Tgmobs+pLPC27tS3gOpEAxAffHrq5w509cvkwTf9pF6cWYbg@mail.gmail.com

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/e8b65986ba0de2daeb5bcedc02fb936b04fe464c

Modified Files
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doc/src/sgml/ref/create_table.sgml | 11 ++++---
src/backend/parser/parse_utilcmd.c | 48 ++++++++++++++++++++++++++++++
src/test/regress/expected/create_table.out | 12 ++++----
src/test/regress/expected/inherit.out | 4 +--
src/test/regress/expected/insert.out | 35 +++++++++++++++-------
src/test/regress/sql/create_table.sql | 6 ++--
src/test/regress/sql/inherit.sql | 4 +--
src/test/regress/sql/insert.sql | 19 +++++++-----
8 files changed, 102 insertions(+), 37 deletions(-)