Explicitly set default value for MediaStream.VideoRangeType enum

MediaBrowser.Model/Entities/MediaStream.cs

@@ -172,6 +172,7 @@ namespace MediaBrowser.Model.Entities
         /// Gets the video range type.
         /// </summary>
         /// <value>The video range type.</value>
+        [DefaultValue(VideoRangeType.Unknown)]
         public VideoRangeType VideoRangeType
         {
             get