Pushed some code at jacobemerick/comment-service.
- 4289a63 Adds serializers to DI.
- f8e3487 Injects serializers instead of internal instantiation.
- 96b2207 Unit tests respect the serializer.
- 5a50176 Simplifies mocked data.
- 04c8de8 Finishes serializer changes through tests - no more skips!.