Update release notes for 8.0.2.
Update release notes for 8.0.2.

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