pgsql: Change on-disk representation of NUMERIC datatype so that the

Log Message:
-----------
Change on-disk representation of NUMERIC datatype so that the sign_dscale
word comes before the weight instead of after.  This will allow future
binary-compatible extension of the representation to support compact formats,
as discussed on pgsql-hackers around 2007/06/18.  The reason to do it now is
that we've already pretty well broken any chance of simple in-place upgrade
from 8.2 to 8.3, but it's possible that 8.3 to 8.4 (or whenever we get around
to squeezing NUMERIC) could otherwise be data-compatible.

Modified Files:
--------------
    pgsql/src/include/catalog:
        catversion.h (r1.428 -> r1.429)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/catversion.h?r1=1.428&r2=1.429)
    pgsql/src/include/utils:
        numeric.h (r1.24 -> r1.25)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/utils/numeric.h?r1=1.24&r2=1.25)