New Series Relation - Edition (#1583)

* Moved UpdateRelatedSeries from controller to SeriesService.cs

* Added 2 tests.
- UpdateRelatedSeries_ShouldDeletePrequelRelation
- UpdateRelatedSeries_ShouldNotAllowDuplicates

* Some docs and codestyle nitpicks

* Simplified tests and made easier to read

* Added 'Editions' series relation

* Missing code to properly show the relations in the UI

* Create Service for GetRelatedServices

* Added unit test. Assert Edition, Prequel and Sequel do not return parent while others do

* fixed missing userRating

* Add requested changes:
- Rename one test
- Split one test into two tests

API/DTOs/SeriesDetail/RelatedSeriesDto.cs

@@ -22,4 +22,5 @@ public class RelatedSeriesDto
     public IEnumerable<SeriesDto> AlternativeVersions { get; set; }
     public IEnumerable<SeriesDto> Doujinshis { get; set; }
     public IEnumerable<SeriesDto> Parent { get; set; }
+    public IEnumerable<SeriesDto> Editions { get; set; }
 }

API/DTOs/SeriesDetail/UpdateRelatedSeriesDto.cs

@@ -16,4 +16,5 @@ public class UpdateRelatedSeriesDto
     public IList<int> AlternativeSettings { get; set; }
     public IList<int> AlternativeVersions { get; set; }
     public IList<int> Doujinshis { get; set; }
+    public IList<int> Editions { get; set; }
 }