Update README.md

Author: brianmc

README.md

@@ -33,20 +33,15 @@ require 'vendor/autoload.php';
 ```json
 {
   "require": {
-  "php": ">=5.2.0",
+  "php": ">=5.5",
   "ext-curl": "*",
-  "authorizenet/authorizenet": "1.8.8",
-  "jms/serializer": "xsd2php-dev as 0.18.0"
-},
-"require-dev": {
-  "goetas/xsd2php": "2.*@dev",
-  "goetas/xsd-reader": "2.*@dev"
-},
-"repositories": [{
-    "type": "vcs",
-    "url": "https://github.com/goetas/serializer.git"
-    }]
-
+  "authorizenet/authorizenet": "1.8.9",
+  "jms/serializer": "serializer-master-dev as 1.0"
+  },
+  "repositories": [{
+       "type": "vcs",
+       "url": "https://github.com/goetas/serializer.git"
+  }]
 }
 ```