Avatar Destroy (#319)

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## [TICKETID](https://ready-player-me.atlassian.net/browse/TICKETID)

## Description

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Author: srcnalt

Runtime/Core/Scripts/Data/AvatarData.cs

@@ -1,10 +1,43 @@
-using UnityEngine;
+using System;
+using UnityEngine;
 
 namespace ReadyPlayerMe.Core
 {
     public class AvatarData : MonoBehaviour
     {
         public string AvatarId;
         public AvatarMetadata AvatarMetadata;
+
+        private SkinnedMeshRenderer[] meshes;
+
+        private void Awake()
+        {
+            meshes = GetComponentsInChildren<SkinnedMeshRenderer>();
+        }
+
+        private void OnDestroy()
+        {
+            foreach (var mesh in meshes)
+            {
+                var materials = mesh.sharedMaterials;
+
+                foreach (var material in materials)
+                {
+                    if(material == null) continue;
+                    
+                    foreach (var property in material.GetTexturePropertyNames())
+                    {
+                        Texture texture = material.GetTexture(property);
+                        
+                        if(texture == null) continue;
+                        
+                        Destroy(texture); 
+                    }
+                    Destroy(material);
+                }
+                
+                Destroy(mesh.sharedMesh);
+            }
+        }
     }
 }