Clarify wording on when ctid is modified by VACUUM FULL.
Clarify wording on when ctid is modified by VACUUM FULL.

cjcjameson/gpdb,rvs/gpdb,lintzc/gpdb,edespino/gpdb,edespino/gpdb,0x0FFF/gpdb,yuanzhao/gpdb,edespino/gpdb,foyzur/gpdb,ahachete/gpdb,xuegang/gpdb,Chibin/gpdb,0x0FFF/gpdb,ahachete/gpdb,oberstet/postgres-xl,adam8157/gpdb,jmcatamney/gpdb,tangp3/gpdb,yuanzhao/gpdb,Chibin/gpdb,rubikloud/gpdb,postmind-net/postgres-xl,yazun/postgres-xl,jmcatamney/gpdb,adam8157/gpdb,pavanvd/postgres-xl,lisakowen/gpdb,lpetrov-pivotal/gpdb,rubikloud/gpdb,CraigHarris/gpdb,janebeckman/gpdb,atris/gpdb,jmcatamney/gpdb,xinzweb/gpdb,foyzur/gpdb,postmind-net/postgres-xl,janebeckman/gpdb,zaksoup/gpdb,Quikling/gpdb,lisakowen/gpdb,arcivanov/postgres-xl,oberstet/postgres-xl,postmind-net/postgres-xl,Quikling/gpdb,xinzweb/gpdb,50wu/gpdb,zeroae/postgres-xl,janebeckman/gpdb,lisakowen/gpdb,lintzc/gpdb,snaga/postgres-xl,zaksoup/gpdb,rvs/gpdb,Chibin/gpdb,ashwinstar/gpdb,xuegang/gpdb,rubikloud/gpdb,randomtask1155/gpdb,arcivanov/postgres-xl,kaknikhil/gpdb,adam8157/gpdb,adam8157/gpdb,xinzweb/gpdb,atris/gpdb,kaknikhil/gpdb,techdragon/Postgres-XL,rubikloud/gpdb,rubikloud/gpdb,yuanzhao/gpdb,ahachete/gpdb,50wu/gpdb,yuanzhao/gpdb,kaknikhil/gpdb,greenplum-db/gpdb,tangp3/gpdb,50wu/gpdb,randomtask1155/gpdb,greenplum-db/gpdb,adam8157/gpdb,greenplum-db/gpdb,oberstet/postgres-xl,edespino/gpdb,tangp3/gpdb,arcivanov/postgres-xl,pavanvd/postgres-xl,zaksoup/gpdb,edespino/gpdb,ovr/postgres-xl,lintzc/gpdb,ahachete/gpdb,tangp3/gpdb,lintzc/gpdb,0x0FFF/gpdb,rvs/gpdb,Chibin/gpdb,ovr/postgres-xl,snaga/postgres-xl,zaksoup/gpdb,lpetrov-pivotal/gpdb,rubikloud/gpdb,CraigHarris/gpdb,tpostgres-projects/tPostgres,xuegang/gpdb,chrishajas/gpdb,Quikling/gpdb,royc1/gpdb,edespino/gpdb,xinzweb/gpdb,techdragon/Postgres-XL,ashwinstar/gpdb,cjcjameson/gpdb,randomtask1155/gpdb,royc1/gpdb,janebeckman/gpdb,pavanvd/postgres-xl,0x0FFF/gpdb,royc1/gpdb,lintzc/gpdb,royc1/gpdb,pavanvd/postgres-xl,ahachete/gpdb,royc1/gpdb,CraigHarris/gpdb,lpetrov-pivotal/gpdb,ashwinstar/gpdb,foyzur/gpdb,Quikling/gpdb,randomtask1155/gpdb,ovr/postgres-xl,zaksoup/gpdb,lisakowen/gpdb,royc1/gpdb,atris/gpdb,janebeckman/gpdb,randomtask1155/gpdb,xuegang/gpdb,50wu/gpdb,xinzweb/gpdb,Quikling/gpdb,kaknikhil/gpdb,foyzur/gpdb,oberstet/postgres-xl,janebeckman/gpdb,xuegang/gpdb,randomtask1155/gpdb,adam8157/gpdb,greenplum-db/gpdb,50wu/gpdb,techdragon/Postgres-XL,jmcatamney/gpdb,CraigHarris/gpdb,jmcatamney/gpdb,CraigHarris/gpdb,rvs/gpdb,50wu/gpdb,xuegang/gpdb,zaksoup/gpdb,zeroae/postgres-xl,Postgres-XL/Postgres-XL,0x0FFF/gpdb,lpetrov-pivotal/gpdb,yuanzhao/gpdb,xinzweb/gpdb,snaga/postgres-xl,oberstet/postgres-xl,edespino/gpdb,edespino/gpdb,atris/gpdb,lpetrov-pivotal/gpdb,lintzc/gpdb,tpostgres-projects/tPostgres,lpetrov-pivotal/gpdb,pavanvd/postgres-xl,kaknikhil/gpdb,tangp3/gpdb,janebeckman/gpdb,kmjungersen/PostgresXL,zaksoup/gpdb,snaga/postgres-xl,randomtask1155/gpdb,xuegang/gpdb,rubikloud/gpdb,Chibin/gpdb,Quikling/gpdb,yuanzhao/gpdb,cjcjameson/gpdb,CraigHarris/gpdb,ahachete/gpdb,jmcatamney/gpdb,arcivanov/postgres-xl,chrishajas/gpdb,cjcjameson/gpdb,chrishajas/gpdb,CraigHarris/gpdb,kmjungersen/PostgresXL,atris/gpdb,kmjungersen/PostgresXL,0x0FFF/gpdb,jmcatamney/gpdb,ashwinstar/gpdb,edespino/gpdb,zeroae/postgres-xl,adam8157/gpdb,50wu/gpdb,ashwinstar/gpdb,Postgres-XL/Postgres-XL,kaknikhil/gpdb,Postgres-XL/Postgres-XL,xuegang/gpdb,greenplum-db/gpdb,chrishajas/gpdb,cjcjameson/gpdb,Quikling/gpdb,tangp3/gpdb,lpetrov-pivotal/gpdb,foyzur/gpdb,snaga/postgres-xl,yazun/postgres-xl,kaknikhil/gpdb,kaknikhil/gpdb,rvs/gpdb,greenplum-db/gpdb,postmind-net/postgres-xl,yuanzhao/gpdb,lisakowen/gpdb,yazun/postgres-xl,foyzur/gpdb,ovr/postgres-xl,yuanzhao/gpdb,Quikling/gpdb,janebeckman/gpdb,postmind-net/postgres-xl,cjcjameson/gpdb,cjcjameson/gpdb,yuanzhao/gpdb,cjcjameson/gpdb,Chibin/gpdb,Chibin/gpdb,lpetrov-pivotal/gpdb,Chibin/gpdb,lintzc/gpdb,rvs/gpdb,Postgres-XL/Postgres-XL,tangp3/gpdb,rubikloud/gpdb,ashwinstar/gpdb,janebeckman/gpdb,zeroae/postgres-xl,atris/gpdb,rvs/gpdb,yazun/postgres-xl,royc1/gpdb,cjcjameson/gpdb,yuanzhao/gpdb,Quikling/gpdb,ashwinstar/gpdb,rvs/gpdb,tpostgres-projects/tPostgres,lisakowen/gpdb,0x0FFF/gpdb,greenplum-db/gpdb,foyzur/gpdb,50wu/gpdb,kaknikhil/gpdb,lintzc/gpdb,atris/gpdb,kaknikhil/gpdb,arcivanov/postgres-xl,zaksoup/gpdb,royc1/gpdb,CraigHarris/gpdb,techdragon/Postgres-XL,ahachete/gpdb,ashwinstar/gpdb,rvs/gpdb,yazun/postgres-xl,foyzur/gpdb,adam8157/gpdb,Quikling/gpdb,xuegang/gpdb,chrishajas/gpdb,rvs/gpdb,Chibin/gpdb,techdragon/Postgres-XL,kmjungersen/PostgresXL,ovr/postgres-xl,tangp3/gpdb,greenplum-db/gpdb,chrishajas/gpdb,lisakowen/gpdb,ahachete/gpdb,zeroae/postgres-xl,kmjungersen/PostgresXL,jmcatamney/gpdb,randomtask1155/gpdb,chrishajas/gpdb,xinzweb/gpdb,Chibin/gpdb,lintzc/gpdb,0x0FFF/gpdb,Postgres-XL/Postgres-XL,edespino/gpdb,tpostgres-projects/tPostgres,atris/gpdb,chrishajas/gpdb,CraigHarris/gpdb,arcivanov/postgres-xl,lisakowen/gpdb,tpostgres-projects/tPostgres,janebeckman/gpdb,cjcjameson/gpdb,xinzweb/gpdb