remove global_define.h and adjust platform header includes

- Remove unused MRMutex
- Remove unused generate_key

common/global_define.h

@@ -17,17 +17,3 @@
 */
 
 #pragma once
-
-// WHY IS THIS UP HERE
-#if defined(_DEBUG) && defined(WIN32)
-	#ifndef _CRTDBG_MAP_ALLOC
-		#include <stdlib.h>
-		#include <crtdbg.h>
-	#endif
-#endif
-
-
-#ifdef _WINDOWS
-	#include <winsock2.h>
-	#include <windows.h>
-#endif