Update changelog and version

Author: witcher112

Assets/PatchKit Patcher/Scripts/Version.cs

@@ -3,7 +3,7 @@ namespace PatchKit.Unity.Patcher
     public static class Version
     {
         public const int Major = 3;
-        public const int Minor = 12;
+        public const int Minor = 13;
         public const int Release = 0;
 
         public static string Value

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## [3.13.0]
+### Added
+- Speed up unpacking app data with multithreading (#1270)
+
 ## [3.12.0]
 ### Added
 - Support for newer versions of Unity (#1191)