Clarify replication items, and define some terms.
Clarify replication items, and define some terms.

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