feat (RateModsAffectFGChanges): Actually implemented

I'm trying to transfer the nITG implementation for now

src/Foreground.cpp

@@ -73,7 +73,7 @@ void Foreground::LoadFromSong( const Song *pSong )
 void Foreground::Update( float fDeltaTime )
 {
 	// Calls to Update() should *not* be scaled by music rate. Undo it.
-	const float fRate = GAMESTATE->m_SongOptions.GetCurrent().m_fMusicRate;
+	const float fRate = PREFSMAN->m_bRateModsAffectTweens ? 1.0f : GAMESTATE->m_SongOptions.GetCurrent().m_fMusicRate;
 
 	for( unsigned i=0; i < m_BGAnimations.size(); ++i )
 	{
@@ -138,7 +138,7 @@ void Foreground::HandleMessage( const Message &msg )
 /*
  * (c) 2004 Glenn Maynard
  * All rights reserved.
- * 
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the
  * "Software"), to deal in the Software without restriction, including
@@ -148,7 +148,7 @@ void Foreground::HandleMessage( const Message &msg )
  * copyright notice(s) and this permission notice appear in all copies of
  * the Software and that both the above copyright notice(s) and this
  * permission notice appear in supporting documentation.
- * 
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF