added user data save reason

MediaBrowser.Model/Entities/UserDataSaveReason.cs

@@ -0,0 +1,30 @@
+
+namespace MediaBrowser.Model.Entities
+{
+    /// <summary>
+    /// Enum UserDataSaveReason
+    /// </summary>
+    public enum UserDataSaveReason
+    {
+        /// <summary>
+        /// The playback start
+        /// </summary>
+        PlaybackStart,
+        /// <summary>
+        /// The playback progress
+        /// </summary>
+        PlaybackProgress,
+        /// <summary>
+        /// The playback finished
+        /// </summary>
+        PlaybackFinished,
+        /// <summary>
+        /// The toggle played
+        /// </summary>
+        TogglePlayed,
+        /// <summary>
+        /// The update user rating
+        /// </summary>
+        UpdateUserRating
+    }
+}