Charter/Editor additions and fixes (#793)

* camera highlights again

* option to mute all hitsounds

* context menus inside context menus and wip sliders in context menu

* wip volume slider stuff

* strumline preview fix with resizable editors

* more slider stuff

* editor sfx option should now actually work for everything

* fixed strumline vocals volume, fixed note type option keybinds and moved bookmarks and note types into submenus

* fix for saving difficulty specific meta json

* some extra misc changes

fixed camera highlights not updating when zooming in/out, optimized some of the highlight draw code so it doesn't do a full loop, and added the note scale flag into the strumline preview

* fix compiling after merge

source/funkin/editors/ui/UIDropDown.hx

@@ -87,7 +87,7 @@ class UIDropDown extends UISliceSprite {
 	}
 
 	public function openContextMenu() {
-		FlxG.sound.play(Paths.sound(Flags.DEFAULT_EDITOR_DROPDOWNAPPEAR_SOUND));
+		UIState.playEditorSound(Flags.DEFAULT_EDITOR_DROPDOWNAPPEAR_SOUND);
 		var screenPos = getScreenPosition(null, __lastDrawCameras[0] == null ? FlxG.camera : __lastDrawCameras[0]);
 		curMenu = UIState.state.openContextMenu([
 			for(k=>o in items) {