pgsql: Add --min-xid-age and --min-mxid-age options to vacuumdb

Add --min-xid-age and --min-mxid-age options to vacuumdb

These two new options can be used to improve the selectivity of
relations to vacuum or analyze even further depending on the age of
respectively their transaction ID or multixact ID, so as it is possible
to prioritize tables to prevent wraparound of one or the other.
Combined with --table, it is possible to target a subset of tables to
choose as potential processing targets.

Author: Nathan Bossart
Reviewed-by: Michael Paquier, Masahiko Sawada
Discussion: /messages/by-id/FFE5373C-E26A-495B-B5C8-911EC4A41C5E@amazon.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/00d1e88d36687ceae1be2317fac90e967941c085

Modified Files
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doc/src/sgml/ref/vacuumdb.sgml | 54 +++++++++++++++++++++++++++
src/bin/scripts/t/100_vacuumdb.pl | 19 +++++++++-
src/bin/scripts/vacuumdb.c | 77 ++++++++++++++++++++++++++++++++++++++-
3 files changed, 148 insertions(+), 2 deletions(-)