REL_14_21
Fix failure with lock mode used for custom relation options
Fix back-patch of "Under has_wal_read_bug, skip .../001_wal.pl."
Bloom index contrib module
Fix instability in contrib/bloom TAP tests.
Update copyright for 2021
Replace RelationOpenSmgr() with RelationGetSmgr().
Minor fixes in contrib installation scripts.
Pass down "logically unchanged index" hint.
Count contrib/bloom index scans in pgstat view.
Remove redundant memset(0) calls for page init of some index AMs