pgsql: Remove old-style win32 client-only visual c++ build

Log Message:
-----------
Remove old-style win32 client-only visual c++ build infrastructure for everything except
libpq. We need to keep libpq to build static libraries and to use PQtrace
with clients using older versions of MSVC.

Modified Files:
--------------
    pgsql/src:
        bcc32.mak (r1.4 -> r1.5)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bcc32.mak.diff?r1=1.4&r2=1.5)
        win32.mak (r1.14 -> r1.15)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/win32.mak.diff?r1=1.14&r2=1.15)

Removed Files:
-------------
    pgsql/src/bin/pg_config:
        win32.mak
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_config/win32.mak)
    pgsql/src/bin/pg_dump:
        win32.mak
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/win32.mak)
    pgsql/src/bin/psql:
        bcc32.mak
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/bcc32.mak)
        win32.mak
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/win32.mak)