pgsql: Finish reverting "recheck_on_update" patch.

Finish reverting "recheck_on_update" patch.

This reverts commit c203d6cf8 and some follow-on fixes, completing the
task begun in commit 5d28c9bd7. If that feature is ever resurrected,
the code will look quite a bit different from this, so it seems best
to start from a clean slate.

The v11 branch is not touched; in that branch, the recheck_on_update
storage option remains present, but nonfunctional and undocumented.

Discussion: https://postgr.es/m/20190114223409.3tcvejfhlvbucrv5@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1c53c4dec3985512f7f2f53c9d76a5295cd0a2dd

Modified Files
--------------
src/backend/access/common/reloptions.c | 45 +------------
src/backend/access/heap/heapam.c | 109 ++----------------------------
src/backend/catalog/index.c | 5 +-
src/backend/utils/cache/relcache.c | 118 ++-------------------------------
src/bin/psql/tab-complete.c | 4 +-
src/include/access/reloptions.h | 2 -
src/include/utils/rel.h | 12 +---
src/include/utils/relcache.h | 3 +-
8 files changed, 21 insertions(+), 277 deletions(-)