Fix bad serials (#304)

- [X] Fixes bad serial calculations
- [X] Tightens HexStrings

Bumps release version
Updates documentation

Projects/Server.Tests/Tests/Utility/HexStringConverterTest.cs

@@ -0,0 +1,26 @@
+using System;
+using Xunit;
+
+namespace Server.Tests.Accounting
+{
+    public class HexStringConverterTest
+    {
+        [Theory]
+        [InlineData("ABCDEF1234", new byte[] { 0xAB, 0xCD, 0xEF, 0x12, 0x34 })]
+        public void TestGetBytes(string input, byte[] bytes)
+        {
+            Span<byte> outputBytes = stackalloc byte[input.Length / 2];
+            HexStringConverter.GetBytes(input, outputBytes);
+
+            Assert.Equal(bytes, outputBytes.ToArray());
+            Assert.Equal(input, bytes.ToHexString());
+        }
+
+        [Theory]
+        [InlineData("[AB, CD, EF, 12, 34]", new byte[] { 0xAB, 0xCD, 0xEF, 0x12, 0x34 })]
+        public void TestsGetStringDelimited(string expected, byte[] bytes)
+        {
+            Assert.Equal(expected, bytes.ToDelimitedHexString());
+        }
+    }
+}