Misc Bugfixes (#1373)

* Fixed an issue where signalr cover update events would fire before the covers were updated in db and hence UI would show as if no cover for quite some time.

* Refactored MetadataService to GenerateCovers, as that is what this service does.

* Fixed a bug where list item for books that have 0.X series index wouldn't render on series detail. Added Name updates on volume on scan

* Removed some debug code

API/DTOs/VolumeDto.cs

@@ -1,6 +1,7 @@
 
 using System;
 using System.Collections.Generic;
+using API.Entities;
 using API.Entities.Interfaces;
 
 namespace API.DTOs
@@ -8,7 +9,9 @@ namespace API.DTOs
     public class VolumeDto : IHasReadTimeEstimate
     {
         public int Id { get; set; }
+        /// <inheritdoc cref="Volume.Number"/>
         public int Number { get; set; }
+        /// <inheritdoc cref="Volume.Name"/>
         public string Name { get; set; }
         public int Pages { get; set; }
         public int PagesRead { get; set; }