Add info on pgport linking requirements.
Add info on pgport linking requirements.

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