pgsql: Change the name of the Result Cache node to Memoize

Change the name of the Result Cache node to Memoize

"Result Cache" was never a great name for this node, but nobody managed
to come up with another name that anyone liked enough.  That was until
David Johnston mentioned "Node Memoization", which Tom Lane revised to
just "Memoize".  People seem to like "Memoize", so let's do the rename.

Reviewed-by: Justin Pryzby
Discussion: https://postgr.es/m/20210708165145.GG1176@momjian.us
Backpatch-through: 14, where Result Cache was introduced

Branch
------
REL_14_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/47ca4836441d1c24f75a94d43af8bd72d4c8d057

Modified Files
--------------
contrib/postgres_fdw/expected/postgres_fdw.out     |   6 +-
contrib/postgres_fdw/sql/postgres_fdw.sql          |   4 +-
doc/src/sgml/config.sgml                           |   8 +-
doc/src/sgml/release-14.sgml                       |   2 +-
src/backend/commands/explain.c                     |  65 ++-
src/backend/executor/Makefile                      |   2 +-
src/backend/executor/execAmi.c                     |   6 +-
src/backend/executor/execParallel.c                |  21 +-
src/backend/executor/execProcnode.c                |  12 +-
.../executor/{nodeResultCache.c => nodeMemoize.c}  | 486 ++++++++++-----------
src/backend/nodes/copyfuncs.c                      |  12 +-
src/backend/nodes/outfuncs.c                       |  16 +-
src/backend/nodes/readfuncs.c                      |  12 +-
src/backend/optimizer/README                       |   2 +-
src/backend/optimizer/path/allpaths.c              |   6 +-
src/backend/optimizer/path/costsize.c              |  42 +-
src/backend/optimizer/path/joinpath.c              |  86 ++--
src/backend/optimizer/plan/createplan.c            |  49 +--
src/backend/optimizer/plan/initsplan.c             |  18 +-
src/backend/optimizer/plan/setrefs.c               |  14 +-
src/backend/optimizer/plan/subselect.c             |   4 +-
src/backend/optimizer/util/pathnode.c              |  56 ++-
src/backend/utils/misc/guc.c                       |   6 +-
src/backend/utils/misc/postgresql.conf.sample      |   2 +-
src/include/executor/nodeMemoize.h                 |  32 ++
src/include/executor/nodeResultCache.h             |  32 --
src/include/nodes/execnodes.h                      |  48 +-
src/include/nodes/nodes.h                          |   6 +-
src/include/nodes/pathnodes.h                      |  12 +-
src/include/nodes/plannodes.h                      |   6 +-
src/include/optimizer/cost.h                       |   2 +-
src/include/optimizer/pathnode.h                   |  14 +-
src/test/regress/expected/aggregates.out           |   4 +-
src/test/regress/expected/join.out                 |  24 +-
.../expected/{resultcache.out => memoize.out}      |  30 +-
src/test/regress/expected/partition_prune.out      |   4 +-
src/test/regress/expected/subselect.out            |   2 +-
src/test/regress/expected/sysviews.out             |   2 +-
src/test/regress/parallel_schedule                 |   2 +-
src/test/regress/sql/aggregates.sql                |   4 +-
src/test/regress/sql/join.sql                      |   4 +-
.../regress/sql/{resultcache.sql => memoize.sql}   |  16 +-
src/test/regress/sql/partition_prune.sql           |   4 +-
src/tools/pgindent/typedefs.list                   |  20 +-
44 files changed, 597 insertions(+), 608 deletions(-)