pgsql: Fix various instances of "the the".

Log Message:
-----------
Fix various instances of "the the".

Two of these were pointed out by Erik Rijkers; the rest I found.

Modified Files:
--------------
    pgsql/contrib/cube:
        CHANGES (r1.3 -> r1.4)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/contrib/cube/CHANGES?r1=1.3&r2=1.4)
    pgsql/doc/src/sgml:
        pgbench.sgml (r1.14 -> r1.15)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/pgbench.sgml?r1=1.14&r2=1.15)
        pgfreespacemap.sgml (r2.5 -> r2.6)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/pgfreespacemap.sgml?r1=2.5&r2=2.6)
    pgsql/doc/src/sgml/ref:
        copy.sgml (r1.96 -> r1.97)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/copy.sgml?r1=1.96&r2=1.97)
    pgsql/src/backend/access/heap:
        README.HOT (r1.5 -> r1.6)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/heap/README.HOT?r1=1.5&r2=1.6)
        visibilitymap.c (r1.9 -> r1.10)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/heap/visibilitymap.c?r1=1.9&r2=1.10)
    pgsql/src/backend/storage/ipc:
        standby.c (r1.18 -> r1.19)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/storage/ipc/standby.c?r1=1.18&r2=1.19)
    pgsql/src/bin/pg_dump:
        pg_backup_archiver.c (r1.183 -> r1.184)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/pg_backup_archiver.c?r1=1.183&r2=1.184)
    pgsql/src/include:
        port.h (r1.131 -> r1.132)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/port.h?r1=1.131&r2=1.132)
    pgsql/src/tools/backend:
        backend_dirs.html (r1.8 -> r1.9)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/tools/backend/backend_dirs.html?r1=1.8&r2=1.9)