Document why pg_upgrade preserves pg_auth.oid (because they are stored in pg_largeobject_metadata).
Document why pg_upgrade preserves pg_auth.oid (because they are stored
in pg_largeobject_metadata).

adam8157/gpdb,ashwinstar/gpdb,50wu/gpdb,ovr/postgres-xl,tpostgres-projects/tPostgres,lisakowen/gpdb,xinzweb/gpdb,adam8157/gpdb,zeroae/postgres-xl,techdragon/Postgres-XL,ashwinstar/gpdb,yazun/postgres-xl,oberstet/postgres-xl,snaga/postgres-xl,ashwinstar/gpdb,greenplum-db/gpdb,xinzweb/gpdb,zeroae/postgres-xl,jmcatamney/gpdb,pavanvd/postgres-xl,50wu/gpdb,xinzweb/gpdb,yazun/postgres-xl,kmjungersen/PostgresXL,yazun/postgres-xl,jmcatamney/gpdb,tpostgres-projects/tPostgres,arcivanov/postgres-xl,ovr/postgres-xl,techdragon/Postgres-XL,snaga/postgres-xl,adam8157/gpdb,Postgres-XL/Postgres-XL,adam8157/gpdb,pavanvd/postgres-xl,50wu/gpdb,50wu/gpdb,greenplum-db/gpdb,postmind-net/postgres-xl,pavanvd/postgres-xl,postmind-net/postgres-xl,greenplum-db/gpdb,ashwinstar/gpdb,yazun/postgres-xl,snaga/postgres-xl,ashwinstar/gpdb,zeroae/postgres-xl,tpostgres-projects/tPostgres,xinzweb/gpdb,techdragon/Postgres-XL,ashwinstar/gpdb,50wu/gpdb,Postgres-XL/Postgres-XL,arcivanov/postgres-xl,jmcatamney/gpdb,arcivanov/postgres-xl,50wu/gpdb,adam8157/gpdb,tpostgres-projects/tPostgres,jmcatamney/gpdb,greenplum-db/gpdb,greenplum-db/gpdb,ashwinstar/gpdb,snaga/postgres-xl,ovr/postgres-xl,pavanvd/postgres-xl,kmjungersen/PostgresXL,arcivanov/postgres-xl,ovr/postgres-xl,kmjungersen/PostgresXL,kmjungersen/PostgresXL,jmcatamney/gpdb,snaga/postgres-xl,yazun/postgres-xl,greenplum-db/gpdb,adam8157/gpdb,Postgres-XL/Postgres-XL,lisakowen/gpdb,postmind-net/postgres-xl,Postgres-XL/Postgres-XL,greenplum-db/gpdb,adam8157/gpdb,ovr/postgres-xl,jmcatamney/gpdb,tpostgres-projects/tPostgres,oberstet/postgres-xl,postmind-net/postgres-xl,xinzweb/gpdb,lisakowen/gpdb,lisakowen/gpdb,jmcatamney/gpdb,greenplum-db/gpdb,postmind-net/postgres-xl,xinzweb/gpdb,zeroae/postgres-xl,50wu/gpdb,oberstet/postgres-xl,jmcatamney/gpdb,ashwinstar/gpdb,lisakowen/gpdb,pavanvd/postgres-xl,oberstet/postgres-xl,techdragon/Postgres-XL,Postgres-XL/Postgres-XL,adam8157/gpdb,lisakowen/gpdb,techdragon/Postgres-XL,zeroae/postgres-xl,50wu/gpdb,lisakowen/gpdb,oberstet/postgres-xl,arcivanov/postgres-xl,kmjungersen/PostgresXL,arcivanov/postgres-xl,lisakowen/gpdb,xinzweb/gpdb,xinzweb/gpdb