top: minor refactor in preparation for other filtering

While it's only documented (so far) in commit text and
an occasional email I've tried to maintain some coding
standards primarily for reference/navigation purposes.
They also served, I felt, as useful mental challenges.

Someday I will get around to formerly documenting them
but in the meantime here are the ones for this commit:

. functions are grouped into logical (i hope) sections
. functions & sections are ordered to avoid prototypes
. function names are alphabetical within every section

Thus, given those constraints/objectives, and in order
to prepare for an upcoming Other_Filter feature, a few
things had to be renamed and rearranged. Plus a couple
of other (unrelated) tweaks were made for consistency.

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

Reference(s):
commit 270e8e7eeb
http://www.freelists.org/post/procps/PATCH-12-top-restore-terminal-state-on-exit,4

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

top/top_nls.c

@@ -19,9 +19,6 @@
 
 #include <locale.h>
 #include <stdio.h>
-#ifdef VALIDATE_NLS
-#include <stdlib.h>
-#endif
 #include <string.h>
 
 #include "../include/nls.h"
@@ -29,6 +26,10 @@
 #include "top.h"
 #include "top_nls.h"
 
+#ifdef VALIDATE_NLS
+#include <stdlib.h>
+#endif
+
         // Programmer Note(s):
         //  Preparation ---------------------------------------------
         //    Unless you have *something* following the gettext macro,