Fixed a bug in ScanLibrary that caused duplicated Volumes. Implemented APIs for navigating down to Volume for webui.

This is rough code and needs to be polished and refactored.

API/Controllers/SeriesController.cs

@@ -0,0 +1,39 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using API.DTOs;
+using API.Interfaces;
+using AutoMapper;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Logging;
+
+namespace API.Controllers
+{
+    public class SeriesController : BaseApiController
+    {
+        private readonly ILogger<SeriesController> _logger;
+        private readonly IMapper _mapper;
+        private readonly ITaskScheduler _taskScheduler;
+        private readonly ISeriesRepository _seriesRepository;
+
+        public SeriesController(ILogger<SeriesController> logger, IMapper mapper, 
+            ITaskScheduler taskScheduler, ISeriesRepository seriesRepository)
+        {
+            _logger = logger;
+            _mapper = mapper;
+            _taskScheduler = taskScheduler;
+            _seriesRepository = seriesRepository;
+        }
+        
+        [HttpGet("{seriesId}")]
+        public async Task<ActionResult<SeriesDto>> GetSeries(int seriesId)
+        {
+            return Ok(await _seriesRepository.GetSeriesByIdAsync(seriesId));
+        }
+
+        [HttpGet("volumes")]
+        public async Task<ActionResult<IEnumerable<VolumeDto>>> GetVolumes(int seriesId)
+        {
+            return Ok(await _seriesRepository.GetVolumesAsync(seriesId));
+        }
+    }
+}