CLEANUP: include: tree-wide alphabetical sort of include files

This patch fixes all the leftovers from the include cleanup campaign. There
were not that many (~400 entries in ~150 files) but it was definitely worth
doing it as it revealed a few duplicates.
diff --git a/src/applet.c b/src/applet.c
index 3ec106c..a806eca 100644
--- a/src/applet.c
+++ b/src/applet.c
@@ -13,8 +13,8 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-#include <haproxy/applet.h>
 #include <haproxy/api.h>
+#include <haproxy/applet.h>
 #include <haproxy/channel.h>
 #include <haproxy/list.h>
 #include <haproxy/stream.h>