PORT: Allows Markings to Set Custom Layers for Specific Sprites (#2516)

* multilayer markings

* vestigial reptilian tail sprites added

* i fix :)

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Co-authored-by: mq <113324899+mqole@users.noreply.github.com>

Content.Shared/Humanoid/HumanoidVisualLayersExtension.cs

@@ -67,6 +67,9 @@ namespace Content.Shared.Humanoid
                 case HumanoidVisualLayers.Chest:
                     yield return HumanoidVisualLayers.Chest;
                     yield return HumanoidVisualLayers.Tail;
+                    yield return HumanoidVisualLayers.TailBehind;
+                    yield return HumanoidVisualLayers.TailBehindBackpack;
+                    yield return HumanoidVisualLayers.TailOversuit;
                     break;
                 default:
                     yield break;