pgsql: Add logical replication support to replicate into partitioned ta

Add logical replication support to replicate into partitioned tables

Mainly, this adds support code in logical/worker.c for applying
replicated operations whose target is a partitioned table to its
relevant partitions.

Author: Amit Langote <amitlangote09(at)gmail(dot)com>
Reviewed-by: Rafia Sabih <rafia(dot)pghackers(at)gmail(dot)com>
Reviewed-by: Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)com>
Reviewed-by: Petr Jelinek <petr(at)2ndquadrant(dot)com>
Discussion: https://www.postgresql.org/message-id/flat/CA+HiwqH=Y85vRK3mOdjEkqFK+E=ST=eQiHdpj43L=_eJMOOznQ(at)mail(dot)gmail(dot)com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f1ac27bfda6ce8a399d8001843e9aefff5814f9b

Modified Files
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doc/src/sgml/logical-replication.sgml | 17 +-
src/backend/executor/execReplication.c | 14 +-
src/backend/replication/logical/relation.c | 189 +++++++++++++++++
src/backend/replication/logical/tablesync.c | 1 -
src/backend/replication/logical/worker.c | 316 +++++++++++++++++++++++++++-
src/include/replication/logicalrelation.h | 2 +
src/test/subscription/t/013_partition.pl | 166 +++++++++++----
7 files changed, 636 insertions(+), 69 deletions(-)