move child definitions to db

MediaBrowser.Controller/Persistence/IItemRepository.cs

@@ -13,6 +13,12 @@ namespace MediaBrowser.Controller.Persistence
     /// </summary>
     public interface IItemRepository : IRepository
     {
+        /// <summary>
+        /// Opens the connection to the repository
+        /// </summary>
+        /// <returns>Task.</returns>
+        Task Initialize();
+
         /// <summary>
         /// Saves an item
         /// </summary>
@@ -75,6 +81,22 @@ namespace MediaBrowser.Controller.Persistence
         /// <param name="cancellationToken">The cancellation token.</param>
         /// <returns>Task.</returns>
         Task SaveChapters(Guid id, IEnumerable<ChapterInfo> chapters, CancellationToken cancellationToken);
+
+        /// <summary>
+        /// Gets the children.
+        /// </summary>
+        /// <param name="parentId">The parent id.</param>
+        /// <returns>IEnumerable{ChildDefinition}.</returns>
+        IEnumerable<ChildDefinition> GetChildren(Guid parentId);
+
+        /// <summary>
+        /// Saves the children.
+        /// </summary>
+        /// <param name="parentId">The parent id.</param>
+        /// <param name="children">The children.</param>
+        /// <param name="cancellationToken">The cancellation token.</param>
+        /// <returns>Task.</returns>
+        Task SaveChildren(Guid parentId, IEnumerable<ChildDefinition> children, CancellationToken cancellationToken);
     }
 
     /// <summary>