Refactored archive code into a service so that I can write tests for it.

API/Data/SeriesRepository.cs

@@ -129,10 +129,12 @@ namespace API.Data
                 .Include(vol => vol.Files)
                 .ProjectTo<VolumeDto>(_mapper.ConfigurationProvider)
                 .SingleAsync(vol => vol.Id == volumeId);
-
+            
             var volumeList = new List<VolumeDto>() {volume};
             await AddVolumeModifiers(userId, volumeList);
 
+            volumeList[0].Files = volumeList[0].Files.OrderBy(f => f.Chapter).ToList();
+
             return volumeList[0];
         }