pgsql: Support comments on FOREIGN DATA WRAPPER and SERVER objects.

Support comments on FOREIGN DATA WRAPPER and SERVER objects.

This mostly involves making it work with the objectaddress.c framework,
which does most of the heavy lifting. In that vein, change
GetForeignDataWrapperOidByName to get_foreign_data_wrapper_oid and
GetForeignServerOidByName to get_foreign_server_oid, to match the
pattern we use for other object types.

Robert Haas and Shigeru Hanada

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/50533a6dc515cc3182f52838275c9d2a1f587604

Modified Files
--------------
doc/src/sgml/ref/comment.sgml | 2 +
src/backend/catalog/aclchk.c | 31 ++++++++++-
src/backend/catalog/objectaddress.c | 33 +++++++++++-
src/backend/commands/foreigncmds.c | 4 +-
src/backend/foreign/foreign.c | 82 ++++++++++++++--------------
src/backend/parser/gram.y | 13 +++--
src/backend/utils/adt/acl.c | 4 +-
src/include/foreign/foreign.h | 5 +-
src/include/utils/acl.h | 1 +
src/test/regress/expected/foreign_data.out | 2 +
src/test/regress/sql/foreign_data.sql | 2 +
11 files changed, 124 insertions(+), 55 deletions(-)