pgsql: Add polygon opclass for SP-GiST

Add polygon opclass for SP-GiST

Polygon opclass uses compress method feature of SP-GiST added earlier. For now
it's a single operator class which uses this feature. SP-GiST actually indexes
a bounding boxes of input polygons, so part of supported operations are lossy.
Opclass uses most methods of corresponding opclass over boxes of SP-GiST and
treats bounding boxes as point in 4D-space.

Bump catalog version.

Authors: Nikita Glukhov, Alexander Korotkov with minor editorization by me
Reviewed-By: all authors + Darafei Praliaskouski
Discussion: https://www.postgresql.org/message-id/flat/54907069(dot)1030506(at)sigaev(dot)ru

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ff963b393ca93a71d2f398c4c584b322cd351c2c

Modified Files
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doc/src/sgml/spgist.sgml | 36 +++++
src/backend/utils/adt/geo_ops.c | 3 +-
src/backend/utils/adt/geo_spgist.c | 92 ++++++++++-
src/include/catalog/catversion.h | 2 +-
src/include/catalog/pg_amop.h | 16 ++
src/include/catalog/pg_amproc.h | 6 +
src/include/catalog/pg_opclass.h | 1 +
src/include/catalog/pg_opfamily.h | 1 +
src/include/catalog/pg_proc.h | 5 +
src/include/utils/geo_decls.h | 3 +-
src/test/regress/expected/polygon.out | 238 +++++++++++++++++++++++++++++
src/test/regress/expected/sanity_check.out | 3 +
src/test/regress/sql/polygon.sql | 93 +++++++++++
13 files changed, 491 insertions(+), 8 deletions(-)