pgsql: Stamp release 7.3.18.

Log Message:
-----------
Stamp release 7.3.18.

Security: CVE-2007-0555, CVE-2007-0556

Tags:
----
REL7_3_STABLE

Modified Files:
--------------
    pgsql:
        configure (r1.226.2.28 -> r1.226.2.29)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/configure.diff?r1=1.226.2.28&r2=1.226.2.29)
        configure.in (r1.217.2.26 -> r1.217.2.27)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/configure.in.diff?r1=1.217.2.26&r2=1.217.2.27)
    pgsql/doc:
        bug.template (r1.21.2.19 -> r1.21.2.20)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/bug.template.diff?r1=1.21.2.19&r2=1.21.2.20)
    pgsql/src/include:
        pg_config.h.win32 (r1.8.2.17 -> r1.8.2.18)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/pg_config.h.win32.diff?r1=1.8.2.17&r2=1.8.2.18)
    pgsql/src/interfaces/libpq:
        libpq.rc (r1.9.2.17 -> r1.9.2.18)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/libpq.rc.diff?r1=1.9.2.17&r2=1.9.2.18)