Use version map.

Author: dereuromark

README.md

@@ -15,24 +15,20 @@ configuration data and environment variables hidden. :warning:
 
 ## Requirements
 
-The `master` branch has the following requirements:
-
 * SQLite (pdo_sqlite) or another database driver that CakePHP can talk to. By
   default DebugKit will use SQLite, if you need to use a different database see
   the Database Configuration section below.
 
-## DebugKit for CakePHP 2.x
-
-If you want DebugKit for your 2.x application, you can use the latest `2.2.y` tag or the [2.2 branch](https://github.com/cakephp/debug_kit/tree/2.2).
+For details and older versions see [version map](https://github.com/cakephp/debug_kit/wiki#version-map).
 
 ## Installation
 
 * Install the plugin with [Composer](https://getcomposer.org/) from your CakePHP Project's ROOT directory (where the **composer.json** file is located)
 ```sh
-php composer.phar require --dev cakephp/debug_kit:"~3.0"
+php composer.phar require --dev cakephp/debug_kit:"^4.0"
 ```
 
-* [Load the plugin](http://book.cakephp.org/3.0/en/plugins.html#loading-a-plugin)
+* [Load the plugin](https://book.cakephp.org/4/en/plugins.html#loading-a-plugin)
 ```php
 // src/Application.php
 $this->addPlugin('DebugKit');
@@ -52,24 +48,7 @@ the project, add features, and send [pull
 requests](https://help.github.com/articles/using-pull-requests) or open
 [issues](https://github.com/cakephp/debug_kit/issues).
 
-## Versions
-
-DebugKit has several releases, each compatible with different releases of
-CakePHP. Use the appropriate version by downloading a tag, or checking out the
-correct branch.
-
-* `1.0, 1.1, 1.2` are compatible with CakePHP 1.2.x. These releases of DebugKit
-  will not work with CakePHP 1.3. You can also use the `1.2-branch` for the mos
-  recent updates and bugfixes.
-* `1.3.0` is compatible with CakePHP 1.3.x only. It will not work with CakePHP
-  1.2. You can also use the `1.3` branch to get the most recent updates and
-  bugfixes.
-* `2.2.x` are compatible with CakePHP 2.2.0 and greater. It is a necessary
-  upgrade for people using CakePHP 2.4 as the naming conventions around loggers
-  changed in that release. 2.2.x is not actively being developed.
-* `3.x` is compatible with CakePHP 3.x and is still under active development.
-
-# Documentation
+## Documentation
 
 Documentation for DebugKit can be found in the 
 [CakePHP documentation](https://book.cakephp.org/debugkit/3.x/en/index.html).