have ScreenWithMenuElements play and stop music (instead of ScreenOptions and ScreenSelect)

Add StopMusicOnBack metric

stepmania/Themes/default/metrics.ini

@@ -2403,6 +2403,8 @@ UnderlayOnCommand=
 UnderlayOffCommand=
 CodeNames=
 FirstUpdateCommand=
+PlayMusic=1
+StopMusicOnBack=1
 
 [MenuTimer]
 WarningStart=6
@@ -3163,6 +3165,8 @@ TimerSeconds=0
 [ScreenAttract]
 StartScreen=@ScreenTitleBranch()
 Fallback=ScreenWithMenuElementsBlank
+#TRICKY: ScreenAttract plays its own music according to an attract music counter
+PlayMusic=0
 
 [ScreenWithMenuElementsBlank]
 Fallback=ScreenWithMenuElements
@@ -3763,6 +3767,7 @@ Line5=list,AssistTick
 Line6=list,Rate
 Line7=list,AutoAdjust
 Line8=list,SaveScores
+StopMusicOnBack=0
 
 [ScreenCredits]
 Class=ScreenCredits
@@ -3847,7 +3852,6 @@ HelperY=SCREEN_CENTER_Y+80
 
 [ScreenOptionsMaster]
 Fallback=ScreenOptions
-PlayMusic=1
 
 # Player options
 Speed=12