Sort includes and more cleanup and fixes in util/

kill.c

@@ -1,5 +1,4 @@
 /* See LICENSE file for copyright and license details. */
-#include <sys/wait.h>
 #include <ctype.h>
 #include <errno.h>
 #include <signal.h>
@@ -8,6 +7,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <strings.h>
+#include <sys/wait.h>
 #include <unistd.h>
 
 #include "util.h"