Orthography fixes for new castNode() macro.
Orthography fixes for new castNode() macro.

Clean up hastily-composed comment.  Normalize whitespace.

Erik Rijkers and myself

greenplum-db/gpdb,adam8157/gpdb,ashwinstar/gpdb,xinzweb/gpdb,greenplum-db/gpdb,ashwinstar/gpdb,lisakowen/gpdb,adam8157/gpdb,ashwinstar/gpdb,greenplum-db/gpdb,lisakowen/gpdb,ashwinstar/gpdb,50wu/gpdb,jmcatamney/gpdb,lisakowen/gpdb,xinzweb/gpdb,xinzweb/gpdb,lisakowen/gpdb,adam8157/gpdb,50wu/gpdb,adam8157/gpdb,jmcatamney/gpdb,50wu/gpdb,xinzweb/gpdb,ashwinstar/gpdb,jmcatamney/gpdb,50wu/gpdb,lisakowen/gpdb,xinzweb/gpdb,xinzweb/gpdb,adam8157/gpdb,xinzweb/gpdb,50wu/gpdb,adam8157/gpdb,jmcatamney/gpdb,lisakowen/gpdb,ashwinstar/gpdb,ashwinstar/gpdb,jmcatamney/gpdb,jmcatamney/gpdb,50wu/gpdb,greenplum-db/gpdb,50wu/gpdb,lisakowen/gpdb,greenplum-db/gpdb,greenplum-db/gpdb,ashwinstar/gpdb,greenplum-db/gpdb,adam8157/gpdb,50wu/gpdb,adam8157/gpdb,greenplum-db/gpdb,jmcatamney/gpdb,xinzweb/gpdb,lisakowen/gpdb,jmcatamney/gpdb