Support Symfony 3.0

Author: ruudk

composer.json

@@ -18,7 +18,7 @@
         "simple-bus/message-bus": "~2.0",
         "simple-bus/asynchronous": "~2.0",
         "simple-bus/symfony-bridge": "~4.0",
-        "symfony/framework-bundle": "~2.0"
+        "symfony/framework-bundle": "~2.0|~3.0"
     },
     "suggest": {
         "symfony/monolog-bundle": "For logging messages"