pgsql: Change the rules for inherited CHECK constraints to be

Log Message:
-----------
Change the rules for inherited CHECK constraints to be essentially the same
as those for inherited columns; that is, it's no longer allowed for a child
table to not have a check constraint matching one that exists on a parent.
This satisfies the principle of least surprise (rows selected from the parent
will always appear to meet its check constraints) and eliminates some
longstanding bogosity in pg_dump, which formerly had to guess about whether
check constraints were really inherited or not.

The implementation involves adding conislocal and coninhcount columns to
pg_constraint (paralleling attislocal and attinhcount in pg_attribute)
and refactoring various ALTER TABLE actions to be more like those for
columns.

Alex Hunsaker, Nikhil Sontakke, Tom Lane

Modified Files:
--------------
pgsql/doc/src/sgml:
catalogs.sgml (r2.165 -> r2.166)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/catalogs.sgml?r1=2.165&r2=2.166)
ddl.sgml (r1.81 -> r1.82)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ddl.sgml?r1=1.81&r2=1.82)
pgsql/doc/src/sgml/ref:
alter_table.sgml (r1.98 -> r1.99)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/alter_table.sgml?r1=1.98&r2=1.99)
create_table.sgml (r1.109 -> r1.110)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_table.sgml?r1=1.109&r2=1.110)
pgsql/src/backend/access/common:
tupdesc.c (r1.122 -> r1.123)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/common/tupdesc.c?r1=1.122&r2=1.123)
pgsql/src/backend/bootstrap:
bootparse.y (r1.91 -> r1.92)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/bootstrap/bootparse.y?r1=1.91&r2=1.92)
pgsql/src/backend/catalog:
heap.c (r1.332 -> r1.333)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/heap.c?r1=1.332&r2=1.333)
index.c (r1.296 -> r1.297)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/index.c?r1=1.296&r2=1.297)
pg_constraint.c (r1.40 -> r1.41)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/pg_constraint.c?r1=1.40&r2=1.41)
toasting.c (r1.9 -> r1.10)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/toasting.c?r1=1.9&r2=1.10)
pgsql/src/backend/commands:
cluster.c (r1.173 -> r1.174)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/cluster.c?r1=1.173&r2=1.174)
tablecmds.c (r1.251 -> r1.252)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/tablecmds.c?r1=1.251&r2=1.252)
typecmds.c (r1.117 -> r1.118)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/typecmds.c?r1=1.117&r2=1.118)
pgsql/src/backend/executor:
execMain.c (r1.306 -> r1.307)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/executor/execMain.c?r1=1.306&r2=1.307)
pgsql/src/bin/pg_dump:
common.c (r1.103 -> r1.104)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/common.c?r1=1.103&r2=1.104)
pg_dump.c (r1.489 -> r1.490)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/pg_dump.c?r1=1.489&r2=1.490)
pg_dump.h (r1.139 -> r1.140)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/pg_dump.h?r1=1.139&r2=1.140)
pgsql/src/include/catalog:
catversion.h (r1.457 -> r1.458)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/catversion.h?r1=1.457&r2=1.458)
heap.h (r1.87 -> r1.88)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/heap.h?r1=1.87&r2=1.88)
pg_constraint.h (r1.28 -> r1.29)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_constraint.h?r1=1.28&r2=1.29)
pgsql/src/include/nodes:
parsenodes.h (r1.364 -> r1.365)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/nodes/parsenodes.h?r1=1.364&r2=1.365)
pgsql/src/test/regress/expected:
alter_table.out (r1.105 -> r1.106)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/alter_table.out?r1=1.105&r2=1.106)
inherit.out (r1.23 -> r1.24)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/inherit.out?r1=1.23&r2=1.24)
pgsql/src/test/regress/sql:
alter_table.sql (r1.57 -> r1.58)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/sql/alter_table.sql?r1=1.57&r2=1.58)
inherit.sql (r1.11 -> r1.12)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/sql/inherit.sql?r1=1.11&r2=1.12)