Add option to hide default background in lists

Author: vanifatovvlad

Editor/Elements/TriListElement.cs

@@ -37,6 +37,7 @@ public TriListElement(TriProperty property)
             _showElementLabels = settings?.ShowElementLabels ?? false;
             _reorderableListGui = new ReorderableList(null, _property.ArrayElementType)
             {
+                showDefaultBackground = settings?.ShowDefaultBackground ?? true,
                 draggable = settings?.Draggable ?? true,
                 displayAdd = settings == null || !settings.HideAddButton,
                 displayRemove = settings == null || !settings.HideRemoveButton,

Runtime/Attributes/Collections/ListDrawerSettings.cs

@@ -12,5 +12,6 @@ public class ListDrawerSettingsAttribute : Attribute
         public bool HideRemoveButton { get; set; }
         public bool AlwaysExpanded { get; set; }
         public bool ShowElementLabels { get; set; }
+        public bool ShowDefaultBackground { get; set; } = true;
     }
 }