Replacing Networking (#271)

- [X] Removing Kestrel & Libuv
- [X] Cleaning up NetState
- [X] Removing System.IO.Pipelines
- [X] Cleaning up packet reading
- [X] Adds a maximum of 5000 sockets (configurable) to prevent OOM
- [X] Replaces the AsyncState with a thread-safe wrapped boolean called NetworkState
- [X] Removes Parallel.ForEach (no perf gain)
- [X] Removes custom houses compression on another thread
- [X] Test high load scenarios

Bumps release version

Projects/Server/Utilities/HexStringConverter.cs

@@ -0,0 +1,80 @@
+/*************************************************************************
+ * ModernUO                                                              *
+ * Copyright 2019-2020 - ModernUO Development Team                       *
+ * Email: hi@modernuo.com                                                *
+ * File: HexStringConverter.cs                                           *
+ *                                                                       *
+ * This program is free software: you can redistribute it and/or modify  *
+ * it under the terms of the GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3 of the License, or     *
+ * (at your option) any later version.                                   *
+ *                                                                       *
+ * You should have received a copy of the GNU General Public License     *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+ *************************************************************************/
+
+using System;
+
+namespace Server
+{
+    public class HexStringConverter
+    {
+        public static readonly uint[] m_Lookup32Chars = CreateLookup32Chars();
+
+        private static uint[] CreateLookup32Chars()
+        {
+            var result = new uint[256];
+            for (var i = 0; i < 256; i++)
+            {
+                var s = i.ToString("X2");
+                if (BitConverter.IsLittleEndian)
+                {
+                    result[i] = s[0] + ((uint)s[1] << 16);
+                }
+                else
+                {
+                    result[i] = s[1] + ((uint)s[0] << 16);
+                }
+            }
+
+            return result;
+        }
+
+        public static unsafe string GetString(ReadOnlySpan<byte> bytes)
+        {
+            var result = new string((char)0, bytes.Length * 2);
+            fixed (char* resultP = result)
+            {
+                var resultP2 = (uint*)resultP;
+                for (var i = 0; i < bytes.Length; i++)
+                {
+                    resultP2[i] = m_Lookup32Chars[bytes[i]];
+                }
+            }
+
+            return result;
+        }
+
+        public static unsafe void GetBytes(string str, Span<byte> bytes)
+        {
+            fixed (char* strP = str)
+            {
+                var i = 0;
+                var j = 0;
+                while (i < str.Length)
+                {
+                    int chr1 = strP[i++];
+                    int chr2 = strP[i++];
+                    if (BitConverter.IsLittleEndian)
+                    {
+                        bytes[j++] = (byte)(((chr1 - (chr1 >= 65 ? 55 : 48)) << 4) | (chr2 - (chr2 >= 65 ? 55 : 48)));
+                    }
+                    else
+                    {
+                        bytes[j++] = (byte)((chr1 - (chr1 >= 65 ? 55 : 48)) | ((chr2 - (chr2 >= 65 ? 55 : 48)) << 4));
+                    }
+                }
+            }
+        }
+    }
+}