Added a VirtualFolder entity, a resolver, and a CollectionType property.

MediaBrowser.Model/Entities/BaseItem.cs

@@ -6,6 +6,29 @@ namespace MediaBrowser.Model.Entities
 {
     public abstract class BaseItem : BaseEntity, IHasProviderIds
     {
+        /// <summary>
+        /// Goes up the tree to find the virtual folder parent
+        /// </summary>
+        public VirtualFolder VirtualFolder
+        {
+            get
+            {
+                var vf = this as VirtualFolder;
+
+                if (vf != null)
+                {
+                    return vf;
+                }
+
+                if (Parent != null)
+                {
+                    return Parent.VirtualFolder;
+                }
+
+                return null;
+            }
+        }
+
         public string SortName { get; set; }
 
         /// <summary>