pgsql: In documentation, use "lower case"/"upper case" consistently (use

Log Message:
-----------
In documentation, use "lower case"/"upper case" consistently (use space
between words).

Modified Files:
--------------
    pgsql/doc/src/sgml:
        citext.sgml (r1.3 -> r1.4)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/citext.sgml?r1=1.3&r2=1.4)
        client-auth.sgml (r1.138 -> r1.139)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/client-auth.sgml?r1=1.138&r2=1.139)
        config.sgml (r1.286 -> r1.287)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/config.sgml?r1=1.286&r2=1.287)
        func.sgml (r1.519 -> r1.520)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/func.sgml?r1=1.519&r2=1.520)
        installation.sgml (r1.346 -> r1.347)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/installation.sgml?r1=1.346&r2=1.347)
        libpq.sgml (r1.310 -> r1.311)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/libpq.sgml?r1=1.310&r2=1.311)
        pgcrypto.sgml (r1.8 -> r1.9)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/pgcrypto.sgml?r1=1.8&r2=1.9)
        plpgsql.sgml (r1.153 -> r1.154)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/plpgsql.sgml?r1=1.153&r2=1.154)