Merge pull request #6 from manuelbcd/master

Documentation improvement - thank you @manuelbcd

Author: redthor

README.md

@@ -47,7 +47,10 @@ public function registerBundles()
 Configuration
 =============
 
+Add following configuration lines to config.yml file.
+
 ```yaml
+# app/config/config.yml
 mongo_db_migrations:
  collection_name: "migration_versions"
  database_name: "opensky_devo"