Configure the branch alias

Author: jakzal

composer.json

@@ -31,5 +31,10 @@
             "name": "Jakub Zalas",
             "email": "jakub@zalas.pl"
         }
-    ]
+    ],
+    "extra": {
+        "branch-alias": {
+            "dev-master": "1.x-dev"
+        }
+    }
 }