Remove duplicate episodes from trakt before processing (by season and episode numbers)

Fixed: Better handling of duplicate episodes from trakt

NzbDrone.Core/Tv/RefreshEpisodeService.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using NLog;
+using NzbDrone.Common;
 using NzbDrone.Core.Messaging.Events;
 using NzbDrone.Core.Tv.Events;
 
@@ -36,8 +37,9 @@ namespace NzbDrone.Core.Tv
 
             var updateList = new List<Episode>();
             var newList = new List<Episode>();
+            var dupeFreeRemoteEpisodes = remoteEpisodes.DistinctBy(m => new { m.SeasonNumber, m.EpisodeNumber }).ToList();
 
-            foreach (var episode in remoteEpisodes.OrderBy(e => e.SeasonNumber).ThenBy(e => e.EpisodeNumber))
+            foreach (var episode in dupeFreeRemoteEpisodes.OrderBy(e => e.SeasonNumber).ThenBy(e => e.EpisodeNumber))
             {
                 try
                 {