New: Multi Language selection per indexer

Closes #2854

src/NzbDrone.Core.Test/IndexerTests/TestIndexerSettings.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using NzbDrone.Core.Indexers;
 using NzbDrone.Core.Validation;
 
@@ -12,5 +13,7 @@ namespace NzbDrone.Core.Test.IndexerTests
         }
 
         public string BaseUrl { get; set; }
+
+        public IEnumerable<int> MultiLanguages { get; set; }
     }
 }