top: honor the restrictive, crufty old top rcfile

At one time, new top silently defaulted when an rcfile
was found to be incompatible.  This is exactly what
the old top did.  However, after some discussion it
was decided top should alert the user and thereby
save the system administrator some headaches.

Now, some are upset over the fatal error, proving you
can't please everybody.  But in all fairness, given
the difficulty of customizing old top, any reluctance
to delete an old saved rcfile is understandable.

To ease transition to this new top, old style rcfiles
will now be honored and converted to the new format.
And if not disabled at ./configure time via CFLAGS,
a user will be warned when an old style rcfile is
about to be overwritten using the 'W' command.

Lastly, the config validation logic was enhanced to
help ensure both types of rcfile haven't been edited
manually and possibly made unuseable.

Reported-By: sergio <mailbox@sergio.spb.ru>
Bug-Debian:  http://bugs.debian.org/651213

Reported-By: martin f krafft <madduck@debian.org>
Bug-Debian:  http://bugs.debian.org/651863

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

top/top_nls.h

@@ -76,6 +76,9 @@ enum norm_nls {
    THREADS_show_fmt, TIME_accumed_fmt, UNKNOWN_cmds_txt, UNKNOWN_opts_fmt,
    USAGE_abbrev_txt, WORD_allcpus_txt, WORD_another_txt, WORD_eachcpu_fmt,
    WORD_process_txt, WORD_threads_txt, WRITE_rcfile_fmt, WRONG_switch_fmt,
+#ifndef WARN_CFG_OFF
+   XTRA_warncfg_txt,
+#endif
       norm_MAX
 };