pgsql: Add Charset WIN1252 support.

Log Message:
-----------
Add Charset WIN1252 support.

Roland Volkmann

Modified Files:
--------------
    pgsql/src/backend/utils/mb:
        encnames.c (r1.20 -> r1.21)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/encnames.c.diff?r1=1.20&r2=1.21)
    pgsql/src/include/mb:
        pg_wchar.h (r1.52 -> r1.53)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/mb/pg_wchar.h.diff?r1=1.52&r2=1.53)

Added Files:
-----------
    pgsql/src/backend/utils/mb/Unicode:
        utf8_to_win1252.map (r1.1)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/Unicode/utf8_to_win1252.map?rev=1.1&content-type=text/x-cvsweb-markup)
        win1252_to_utf8.map (r1.1)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/Unicode/win1252_to_utf8.map?rev=1.1&content-type=text/x-cvsweb-markup)
    pgsql/src/backend/utils/mb/conversion_procs/utf8_and_win1252:
        Makefile (r1.1)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/conversion_procs/utf8_and_win1252/Makefile?rev=1.1&content-type=text/x-cvsweb-markup)
        utf8_and_win1252.c (r1.1)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/conversion_procs/utf8_and_win1252/utf8_and_win1252.c?rev=1.1&content-type=text/x-cvsweb-markup)