Unit Tests & New Natural Sort (#941)

* Added a lot of tests

* More tests! Added a Parser.NormalizePath to normalize all paths within Kavita.

* Fixed a bug where MarkChaptersAsUnread implementation wasn't consistent between different files and lead to extra row generation for no reason.

* Added more unit tests

* Found a better implementation for Natural Sorting. Added tests and validate it works. Next commit will swap out natural Sort for new Extension.

* Replaced NaturalSortComparer with OrderByNatural.

* Drastically simplified and sped up FindFirstEntry for finding cover images in archives

* Initial fix for a epub bug where metadata defines key as absolute path but document uses a relative path. We now have a hack to correct for the epub.

API.Tests/Services/DirectoryServiceTests.cs

@@ -776,5 +776,18 @@ namespace API.Tests.Services
 
 
         #endregion
+
+        #region GetHumanReadableBytes
+
+        [Theory]
+        [InlineData(1200, "1.17 KB")]
+        [InlineData(1, "1 B")]
+        [InlineData(10000000, "9.54 MB")]
+        [InlineData(10000000000, "9.31 GB")]
+        public void GetHumanReadableBytesTest(long bytes, string expected)
+        {
+            Assert.Equal(expected, DirectoryService.GetHumanReadableBytes(bytes));
+        }
+        #endregion
     }
 }