pgsql: Make it possibly to specify GUC params per user and per database.

Log Message:
-----------
Make it possibly to specify GUC params per user and per database.

Create a new catalog pg_db_role_setting where they are now stored, and better
encapsulate the code that deals with settings into its realm. The old
datconfig and rolconfig columns are removed.

psql has gained a \drds command to display the settings.

Backwards compatibility warning: while the backwards-compatible system views
still have the config columns, they no longer completely represent the
configuration for a user or database.

Catalog version bumped.

Modified Files:
--------------
pgsql/doc/src/sgml:
catalogs.sgml (r2.208 -> r2.209)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/catalogs.sgml?r1=2.208&r2=2.209)
pgsql/doc/src/sgml/ref:
alter_role.sgml (r1.14 -> r1.15)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/alter_role.sgml?r1=1.14&r2=1.15)
pgsql/src/backend/catalog:
Makefile (r1.72 -> r1.73)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/Makefile?r1=1.72&r2=1.73)
catalog.c (r1.83 -> r1.84)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/catalog.c?r1=1.83&r2=1.84)
pg_shdepend.c (r1.35 -> r1.36)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/pg_shdepend.c?r1=1.35&r2=1.36)
system_views.sql (r1.60 -> r1.61)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/system_views.sql?r1=1.60&r2=1.61)
pgsql/src/backend/commands:
dbcommands.c (r1.226 -> r1.227)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/dbcommands.c?r1=1.226&r2=1.227)
user.c (r1.188 -> r1.189)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/user.c?r1=1.188&r2=1.189)
pgsql/src/backend/nodes:
copyfuncs.c (r1.440 -> r1.441)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/nodes/copyfuncs.c?r1=1.440&r2=1.441)
equalfuncs.c (r1.363 -> r1.364)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/nodes/equalfuncs.c?r1=1.363&r2=1.364)
pgsql/src/backend/parser:
gram.y (r2.680 -> r2.681)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/gram.y?r1=2.680&r2=2.681)
pgsql/src/backend/utils/init:
miscinit.c (r1.177 -> r1.178)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/init/miscinit.c?r1=1.177&r2=1.178)
postinit.c (r1.197 -> r1.198)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/init/postinit.c?r1=1.197&r2=1.198)
pgsql/src/bin/pg_dump:
dumputils.c (r1.49 -> r1.50)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/dumputils.c?r1=1.49&r2=1.50)
dumputils.h (r1.26 -> r1.27)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/dumputils.h?r1=1.26&r2=1.27)
pg_dumpall.c (r1.127 -> r1.128)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/pg_dumpall.c?r1=1.127&r2=1.128)
pgsql/src/bin/psql:
command.c (r1.208 -> r1.209)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/command.c?r1=1.208&r2=1.209)
describe.c (r1.227 -> r1.228)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/describe.c?r1=1.227&r2=1.228)
describe.h (r1.41 -> r1.42)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/describe.h?r1=1.41&r2=1.42)
pgsql/src/include/catalog:
catversion.h (r1.541 -> r1.542)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/catversion.h?r1=1.541&r2=1.542)
dependency.h (r1.41 -> r1.42)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/dependency.h?r1=1.41&r2=1.42)
indexing.h (r1.109 -> r1.110)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/indexing.h?r1=1.109&r2=1.110)
pg_attribute.h (r1.153 -> r1.154)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_attribute.h?r1=1.153&r2=1.154)
pg_authid.h (r1.9 -> r1.10)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_authid.h?r1=1.9&r2=1.10)
pg_database.h (r1.50 -> r1.51)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_database.h?r1=1.50&r2=1.51)
toasting.h (r1.8 -> r1.9)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/toasting.h?r1=1.8&r2=1.9)
pgsql/src/include/nodes:
parsenodes.h (r1.404 -> r1.405)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/nodes/parsenodes.h?r1=1.404&r2=1.405)
pgsql/src/include/utils:
guc.h (r1.106 -> r1.107)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/utils/guc.h?r1=1.106&r2=1.107)
pgsql/src/test/regress/expected:
rules.out (r1.150 -> r1.151)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/rules.out?r1=1.150&r2=1.151)
sanity_check.out (r1.41 -> r1.42)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/sanity_check.out?r1=1.41&r2=1.42)

Added Files:
-----------
pgsql/src/backend/catalog:
pg_db_role_setting.c (r1.1)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/pg_db_role_setting.c?rev=1.1&content-type=text/x-cvsweb-markup)
pgsql/src/include/catalog:
pg_db_role_setting.h (r1.1)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_db_role_setting.h?rev=1.1&content-type=text/x-cvsweb-markup)