IndexerType added, this will store the source indexer in history, so users can see (if they care) and we can add an icon if we want.

NzbDrone.Core/Repository/History.cs

@@ -1,4 +1,5 @@
 using System;
+using NzbDrone.Core.Model;
 using NzbDrone.Core.Repository.Quality;
 using SubSonic.SqlGeneration.Schema;
 
@@ -14,6 +15,7 @@ namespace NzbDrone.Core.Repository
         public QualityTypes Quality { get; set; }
         public DateTime Date { get; set; }
         public bool IsProper { get; set; }
+        public IndexerType? Indexer { get; set; }
         
         [SubSonicToOneRelation(ThisClassContainsJoinKey = true)]
         public virtual Episode Episode { get; protected set; }