OPDS Cleanup (#534)

* Fixed opds url display

* Rewrote how stat collection works, now we check in multiple places and always run stat collection in a background thread, to not block main thread.

* Cleaned up the ParseInfoTest to be more verbose

* Added benchmarking

API.Benchmark/ParseScannedFilesBenchmarks.cs

@@ -0,0 +1,40 @@
+using System;
+using System.IO;
+using API.Entities.Enums;
+using API.Interfaces.Services;
+using API.Services;
+using API.Services.Tasks.Scanner;
+using BenchmarkDotNet.Attributes;
+using BenchmarkDotNet.Order;
+using Microsoft.Extensions.Logging;
+using NSubstitute;
+
+namespace API.Benchmark
+{
+    [MemoryDiagnoser]
+    [Orderer(SummaryOrderPolicy.FastestToSlowest)]
+    [RankColumn]
+    [SimpleJob(launchCount: 1, warmupCount: 3, targetCount: 5, invocationCount: 100, id: "Test"), ShortRunJob]
+    public class ParseScannedFilesBenchmarks
+    {
+        private readonly ParseScannedFiles _parseScannedFiles;
+        private readonly ILogger<ParseScannedFiles> _logger = Substitute.For<ILogger<ParseScannedFiles>>();
+        private readonly ILogger<BookService> _bookLogger = Substitute.For<ILogger<BookService>>();
+
+        public ParseScannedFilesBenchmarks()
+        {
+            IBookService bookService = new BookService(_bookLogger);
+            _parseScannedFiles = new ParseScannedFiles(bookService, _logger);
+        }
+
+        [Benchmark]
+        public void Test()
+        {
+            var libraryPath = Path.Join(Directory.GetCurrentDirectory(),
+                "../../../Services/Test Data/ScannerService/Manga");
+            var parsedSeries = _parseScannedFiles.ScanLibrariesForSeries(LibraryType.Manga, new string[] {libraryPath},
+                out var totalFiles, out var scanElapsedTime);
+        }
+
+    }
+}