pgsql: Test replay of regression tests.

Test replay of regression tests.

Add a new TAP test under src/test/recovery to run the standard
regression tests while a streaming replica replays the WAL. This
provides a basic workout for WAL decoding and redo code, and compares
the replicated result.

Optionally, enable (expensive) wal_consistency_checking if listed in
the env variable PG_TEST_EXTRA.

Reviewed-by: 綱川 貴之 (Takayuki Tsunakawa) <tsunakawa(dot)takay(at)fujitsu(dot)com>
Reviewed-by: Andres Freund <andres(at)anarazel(dot)de>
Reviewed-by: Andrew Dunstan <andrew(at)dunslane(dot)net>
Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Reviewed-by: Anastasia Lubennikova <lubennikovaav(at)gmail(dot)com>
Reviewed-by: Michael Paquier <michael(at)paquier(dot)xyz>
Discussion: https://postgr.es/m/CA%2BhUKGKpRWQ9SxdxxDmTBCJoR0YnFpMBe7kyzY8SUQk%2BHeskxg%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/123828a7fa563025d0ceee10cf1b2a253cd05319

Modified Files
--------------
doc/src/sgml/regress.sgml | 11 +++++
src/test/recovery/Makefile | 6 ++-
src/test/recovery/t/027_stream_regress.pl | 80 +++++++++++++++++++++++++++++++
src/tools/msvc/vcregress.pl | 2 +
4 files changed, 98 insertions(+), 1 deletion(-)