Wrong service provider (#55)

You had added RequestMigrationsMiddleware::class as a service provider in the README.md file. That does not seem right? :)

README.md

@@ -24,7 +24,7 @@ If you are using an earlier version of Laravel or have autoloading disabled you
 
 ```php
 'providers' => [
-    \TomSchlick\RequestMigrations\RequestMigrationsMiddleware::class,
+    \TomSchlick\RequestMigrations\RequestMigrationsServiceProvider.php,
 ]
 ```
 ```php