add a Request::raw_post buffer

This buffer is used when a Function::NeedToCopyRawPost() method returned true.

while here:
- remove WINIX_POST_PARAMS and WINIX_RAW_POST_STRING plugin messages

winixd/functions/functionbase.h

@@ -4,8 +4,8 @@
  * Author: Tomasz Sowa <t.sowa@ttmath.org>
  */
 
-/* 
- * Copyright (c) 2010-2022, Tomasz Sowa
+/*
+ * Copyright (c) 2010-2023, Tomasz Sowa
  * All rights reserved.
  * 
  * Redistribution and use in source and binary forms, with or without
@@ -167,6 +167,7 @@ public:
 	//void SetSynchro(Synchro * psynchro);
 	//void SetSessionManager(SessionManager * pmanager);
 
+	virtual bool NeedToCopyRawPost();
 
 protected: