pgsql: Add regexp_replace() to string functions section.

Log Message:
-----------
Add regexp_replace() to string functions section.

Joachim Wieland

Modified Files:
--------------
    pgsql/doc/src/sgml:
        func.sgml (r1.318 -> r1.319)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/func.sgml.diff?r1=1.318&r2=1.319)
        plpgsql.sgml (r1.90 -> r1.91)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/plpgsql.sgml.diff?r1=1.90&r2=1.91)
    pgsql/src/pl/plpgsql/src:
        pl_comp.c (r1.102 -> r1.103)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/pl/plpgsql/src/pl_comp.c.diff?r1=1.102&r2=1.103)
        pl_exec.c (r1.165 -> r1.166)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/pl/plpgsql/src/pl_exec.c.diff?r1=1.165&r2=1.166)
        pl_funcs.c (r1.48 -> r1.49)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/pl/plpgsql/src/pl_funcs.c.diff?r1=1.48&r2=1.49)
        plpgsql.h (r1.70 -> r1.71)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/pl/plpgsql/src/plpgsql.h.diff?r1=1.70&r2=1.71)
        scan.l (r1.45 -> r1.46)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/pl/plpgsql/src/scan.l.diff?r1=1.45&r2=1.46)
    pgsql/src/test/regress/expected:
        plpgsql.out (r1.45 -> r1.46)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/plpgsql.out.diff?r1=1.45&r2=1.46)
    pgsql/src/test/regress/sql:
        plpgsql.sql (r1.38 -> r1.39)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/sql/plpgsql.sql.diff?r1=1.38&r2=1.39)