Fix issue where loading a new appearance onto an NPC would not remove the previous attachments from the scene.

Addresses http://opensimulator.org/mantis/view.php?id=5636

OpenSim/Region/OptionalModules/World/NPC/NPCModule.cs

@@ -143,6 +143,16 @@ namespace OpenSim.Region.OptionalModules.World.NPC
                 if (!m_avatars.ContainsKey(agentId))
                     return false;
 
+            // FIXME: An extremely bad bit of code that reaches directly into the attachments list and manipulates it
+            List<SceneObjectGroup> attachments = sp.Attachments;
+            lock (attachments)
+            {
+                foreach (SceneObjectGroup att in attachments)
+                    scene.DeleteSceneObject(att, false);
+
+                attachments.Clear();
+            }
+
             AvatarAppearance npcAppearance = new AvatarAppearance(appearance, true);
             sp.Appearance = npcAppearance;
             sp.RezAttachments();