fix master alias (#12)

fix master alias

Author: Kevin Buchholz

composer.json

@@ -55,7 +55,7 @@
     },
     "extra": {
         "branch-alias": {
-            "dev-master": "1.1-dev"
+            "dev-master": "1.2.x-dev"
         },
         "laravel": {
             "providers": [