Log warnings when deleting an episode file and the root folder is missing/empty

Closes #2305

src/NzbDrone.Core/MediaFiles/MediaFileDeletionService.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.IO;
 using System.Net;
 using NLog;
@@ -41,11 +41,13 @@ namespace NzbDrone.Core.MediaFiles
 
             if (!_diskProvider.FolderExists(rootFolder))
             {
+                _logger.Warn("Series' root folder ({0}) doesn't exist.", rootFolder);
                 throw new NzbDroneClientException(HttpStatusCode.Conflict, "Series' root folder ({0}) doesn't exist.", rootFolder);
             }
 
             if (_diskProvider.GetDirectories(rootFolder).Empty())
             {
+                _logger.Warn("Series' root folder ({0}) is empty.", rootFolder);
                 throw new NzbDroneClientException(HttpStatusCode.Conflict, "Series' root folder ({0}) is empty.", rootFolder);
             }