pgsql: Create the system catalog infrastructure needed for KNNGIST.

Create the system catalog infrastructure needed for KNNGIST.

This commit adds columns amoppurpose and amopsortfamily to pg_amop, and
column amcanorderbyop to pg_am. For the moment all the entries in
amcanorderbyop are "false", since the underlying support isn't there yet.

Also, extend the CREATE OPERATOR CLASS/ALTER OPERATOR FAMILY commands with
[ FOR SEARCH | FOR ORDER BY sort_operator_family ] clauses to allow the new
columns of pg_amop to be populated, and create pg_dump support for dumping
that information.

I also added some documentation, although it's perhaps a bit premature
given that the feature doesn't do anything useful yet.

Teodor Sigaev, Robert Haas, Tom Lane

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=725d52d0c27cffe8c99bb78e2b0d2480d5cd702b

Modified Files
--------------
doc/src/sgml/catalogs.sgml | 69 +++-
doc/src/sgml/ref/alter_opfamily.sgml | 18 +-
doc/src/sgml/ref/create_opclass.sgml | 18 +-
doc/src/sgml/xindex.sgml | 65 +++-
src/backend/commands/opclasscmds.c | 78 +++-
src/backend/nodes/copyfuncs.c | 1 +
src/backend/nodes/equalfuncs.c | 1 +
src/backend/optimizer/util/plancat.c | 1 +
src/backend/optimizer/util/predtest.c | 8 +-
src/backend/parser/gram.y | 14 +-
src/backend/utils/cache/lsyscache.c | 15 +-
src/backend/utils/cache/syscache.c | 4 +-
src/bin/pg_dump/pg_dump.c | 163 +++++--
src/include/catalog/catversion.h | 2 +-
src/include/catalog/indexing.h | 2 +-
src/include/catalog/pg_am.h | 58 ++--
src/include/catalog/pg_amop.h | 746 +++++++++++++++---------------
src/include/nodes/parsenodes.h | 1 +
src/include/nodes/relation.h | 1 +
src/test/regress/expected/opr_sanity.out | 69 +++-
src/test/regress/sql/opr_sanity.sql | 54 ++-
21 files changed, 913 insertions(+), 475 deletions(-)