Synchronized source file headers (#3212)

* Alphabetically sorted includes.
* Updated copyright and license text to match across all files.
* Removed pragma once define in header files in lieu of ifdef guards.

src/common/malloc.cpp

@@ -1,14 +1,15 @@
-// Copyright (c) Athena Dev Teams - Licensed under GNU GPL
+// Copyright (c) rAthena Dev Teams - Licensed under GNU GPL
 // For more information, see LICENCE in the main folder
 
 #include "malloc.hpp"
-#include "core.hpp"
-#include "showmsg.hpp"
 
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
 
+#include "core.hpp"
+#include "showmsg.hpp"
+
 #define FREED_POINTER 0xdeadbeafL
 
 ////////////// Memory Libraries //////////////////