Add branch-alias to composer.json

Author: aderuwe

composer.json

@@ -65,5 +65,10 @@
         "silex/silex": "1.0.*@dev",
         "squizlabs/php_codesniffer": "~1.4.4",
         "twig/twig": "~1.12"
+    },
+    "extra": {
+        "branch-alias": {
+            "dev-master": "1.0.x-dev"
+        }
     }
 }