Log Message:
-----------
Document IS DISTINCT FROM in a more obvious place, and add some more
index entries for IS-foo constructs.
Modified Files:
--------------
pgsql/doc/src/sgml:
func.sgml (r1.220 -> r1.221)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/func.sgml.diff?r1=1.220&r2=1.221)
syntax.sgml (r1.95 -> r1.96)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/syntax.sgml.diff?r1=1.95&r2=1.96)