Add DEC and SESSION_USER as reserved words. Move around a few other keywords which were not in the right category. DEC and SESSION_USER are not yet committed to gram.y,  since I'm in the middle of working on JOIN syntax too.
Add DEC and SESSION_USER as reserved words.
Move around a few other keywords which were not in the right category.
DEC and SESSION_USER are not yet committed to gram.y,
 since I'm in the middle of working on JOIN syntax too.

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