A lot of screens have TweenOffScreen functions; SWME has that, and it's not

virtual, so the names are clashing and confusing.  This should probably just
be virtual.  As an incremental step to that, rename all derived TweenOnScreen
and TweenOffScreen screen functions to TweenOursOnScreen and
TweenOursOffScreen.

stepmania/src/ScreenSelectDifficulty.cpp

@@ -116,7 +116,7 @@ void ScreenSelectDifficulty::Init()
 	
 	this->UpdateSelectableChoices();
 
-	TweenOnScreen();
+	TweenOursOnScreen();
 
 	this->SortByDrawOrder();
 }
@@ -134,7 +134,7 @@ void ScreenSelectDifficulty::HandleScreenMessage( const ScreenMessage SM )
 	switch( SM )
 	{
 	case SM_BeginFadingOut:
-		TweenOffScreen();
+		TweenOursOffScreen();
 		SCREENMAN->PostMessageToTopScreen( SM_AllDoneChoosing, SLEEP_AFTER_TWEEN_OFF_SECONDS );	// nofify parent that we're finished
 		StopTimer();
 		break;
@@ -490,7 +490,7 @@ void ScreenSelectDifficulty::MenuStart( PlayerNumber pn )
 	this->PostScreenMessage( SM_BeginFadingOut, SLEEP_AFTER_CHOICE_SECONDS );	// tell our owner it's time to move on
 }
 
-void ScreenSelectDifficulty::TweenOnScreen() 
+void ScreenSelectDifficulty::TweenOursOnScreen() 
 {
 	for( int page=0; page<NUM_PAGES; page++ )
 	{
@@ -517,7 +517,7 @@ void ScreenSelectDifficulty::TweenOnScreen()
 	}
 }
 
-void ScreenSelectDifficulty::TweenOffScreen()
+void ScreenSelectDifficulty::TweenOursOffScreen()
 {	
 	const int page = m_CurrentPage;