Update doc for real object managers

Author: mcfedr

README.md

@@ -12,14 +12,31 @@ This extension provides following features:
 * Provides correct return type for `Doctrine\ORM\EntityManager::find`, `getReference` and `getPartialReference` when `Foo::class` entity class name is provided as the first argument
 * Adds missing `matching` method on `Doctrine\Common\Collections\Collection`. This can be turned off by setting `parameters.doctrine.allCollectionsSelectable` to `false`.
 
-This extension does not yet support custom `repositoryClass` specified for each entity class. However, if your repositories have a common base class, you can configure it in your `phpstan.neon` and PHPStan will see additional methods you define in it:
+If your repositories have a common base class, you can configure it in your `phpstan.neon` and PHPStan will see additional methods you define in it:
 
-```
+```neon
 parameters:
 	doctrine:
 		repositoryClass: MyApp\Doctrine\BetterEntityRepository
 ```
 
+Alternatively, you can provide your entity manager and all custom repositories will be loaded
+
+```neon
+parameters:
+	doctrine:
+		objectManagerLoader: tests/entity-manager.php
+```
+
+For example, in a Symfony project, `entity-manager.php` would look something like this:
+
+```php
+require dirname(__DIR__).'/../config/bootstrap.php';
+$kernel = new Kernel($_SERVER['APP_ENV'], (bool) $_SERVER['APP_DEBUG']);
+$kernel->boot();
+return $kernel->getContainer()->get('doctrine')->getManager();
+```
+
 ## Usage
 
 To use this extension, require it in [Composer](https://getcomposer.org/):