Change get_rule_expr so that when the input is a List, it displays the list elements comma-separated instead of barfing.  This allows elimination of half a dozen redundant copies of that behavior, and also makes the world safe again for pg_get_expr() applied to pg_index.indexprs, per gripe from Alexander Zhiltsov.
Change get_rule_expr so that when the input is a List, it displays the
list elements comma-separated instead of barfing.  This allows elimination
of half a dozen redundant copies of that behavior, and also makes the
world safe again for pg_get_expr() applied to pg_index.indexprs, per gripe
from Alexander Zhiltsov.

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