Thread: pgsql-server: Add trivial NULL statement to plpgsql, for Oracle

Log Message:
-----------
Add trivial NULL statement to plpgsql, for Oracle compatibility.

Modified Files:
--------------
    pgsql-server/doc/src/sgml:
        plpgsql.sgml (r1.45 -> r1.46)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/doc/src/sgml/plpgsql.sgml.diff?r1=1.45&r2=1.46)
    pgsql-server/src/pl/plpgsql/src:
        gram.y (r1.59 -> r1.60)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/pl/plpgsql/src/gram.y.diff?r1=1.59&r2=1.60)