udpated the CHANGELOG for 2.3

Author: fabpot

UPGRADE-2.3.md

@@ -1,5 +1,52 @@
 UPGRADE FROM 2.2 to 2.3
 =======================
 
- * You now have to manually enable the [debug component](http://symfony.com/blog/new-in-symfony-2-3-new-debug-component) in [`web/app_dev.php`](https://github.com/symfony/symfony-standard/blob/2.3/web/app_dev.php)
-   by adding `Debug::enable();` just after including the boostrap cache.
+When upgrading Symfony from 2.2 to 2.3, you need to do the following changes
+to the code that came from the Standard Edition:
+
+ * The debugging tools are not enabled by default anymore and should be added
+   to the
+   [`web/app_dev.php`](https://github.com/symfony/symfony-standard/blob/2.3/web/app_dev.php)
+   front controller manually, just after including the bootstrap cache:
+
+        use Symfony\Component\Debug\Debug;
+
+        Debug::enable();
+
+   You also need to enable debugging in the
+   [`app/console`](https://github.com/symfony/symfony-standard/blob/2.3/app/console)
+   script, after the `$debug` variable is defined:
+
+        use Symfony\Component\Debug\Debug;
+
+        if ($debug) {
+            Debug::enable();
+        }
+
+ * The `parameters.yml` file can now be managed by the
+   `incenteev/composer-parameter-handler` bundle that comes with the 2.3
+   Standard Edition:
+
+    * add `"incenteev/composer-parameter-handler": "~2.0"` to your
+      `composer.json` file;
+
+    * add `/app/config/parameters.yml` to your `.gitignore` file;
+
+    * create a
+      [`app/config/parameters.yml.dist`](https://github.com/symfony/symfony-standard/blob/2.3/app/config/parameters.yml.dist)
+      file with sensible values for all your parameters.
+
+ * It is highly recommended that you switch the minimum stability to `stable`
+   in your `composer.json` file.
+
+ * If you are using Apache, have a look at the new
+   [`.htaccess`](https://github.com/symfony/symfony-standard/blob/2.3/web/.htaccess)
+   configuration and change yours accordingly.
+
+ * In the
+   [`app/autoload.php`](https://github.com/symfony/symfony-standard/blob/2.3/app/autoload.php)
+   file, the section about `intl` should be removed as it is not needed anymore.
+
+You can also have a look at the
+[diff](https://github.com/symfony/symfony-standard/compare/v2.2.0%E2%80%A62.3)
+between the 2.2 version of the Standard Edition and the 2.3 version.