Clarify input/output timezone information. Add detail on exact interpretation of "concatenated date"  for various lengths.
Clarify input/output timezone information.
Add detail on exact interpretation of "concatenated date"
 for various lengths.

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