top: extend command line sort field override provision

In a effort to anticipate a potential future wishlist,
the recent '-o' sort override command line switch will
now support an override of the sort direction as well.

By prepending a '+' or '-' to any valid field name the
user will be able to guarantee a specific desired sort
direction. The '+' forces a high-to-low (normal) order
while a '-' reverses that to yield a low-to-high sort.

Without this addition users would be left to the mercy
of whatever was last specified for Curwin as reflected
in the rcfile or top's default of a high-to-low order.

(everything is perfectly justified plus right margins)
(are completely filled, but of course it must be luck)

Signed-off-by: Jim Warner <james.warner@comcast.net>

top/top.c

@@ -3291,6 +3291,8 @@ static void parse_args (char **args) {
                if (cp[1]) cp++;
                else if (*args) cp = *args++;
                else error_exit(fmtmk(N_fmt(MISSING_args_fmt), ch));
+               if (*cp == '+') { SETw(Curwin, Qsrt_NORMAL); ++cp; }
+               else if (*cp == '-') { OFFw(Curwin, Qsrt_NORMAL); ++cp; }
                for (i = 0; i < P_MAXPFLGS; i++)
                   if (!STRCMP(cp, N_col(i))) break;
                if (i == P_MAXPFLGS)