Add changes for multibyte support in 7.2.
Add changes for multibyte support in 7.2.

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