Make the disabling of the win key during gameplay a toggleable setting.

osu.Game/Configuration/OsuConfigManager.cs

@@ -98,6 +98,7 @@ namespace osu.Game.Configuration
             Set(OsuSetting.ScoreDisplayMode, ScoringMode.Standardised);
 
             Set(OsuSetting.IncreaseFirstObjectVisibility, true);
+            Set(OsuSetting.GameplayDisableWinKey, true);
 
             // Update
             Set(OsuSetting.ReleaseStream, ReleaseStream.Lazer);
@@ -227,6 +228,7 @@ namespace osu.Game.Configuration
         IntroSequence,
         UIHoldActivationDelay,
         HitLighting,
-        MenuBackgroundSource
+        MenuBackgroundSource,
+        GameplayDisableWinKey
     }
 }