Allow graphql 0.6.0 (#243)

Closes #228

Author: ekosz

package.json

@@ -34,12 +34,12 @@
   "homepage": "https://github.com/mickhansen/graphql-sequelize",
   "dependencies": {
     "babel-runtime": "^6.0.8",
-    "graphql-relay": "^0.4.1",
+    "graphql-relay": "^0.4.2",
     "invariant": "2.2.1",
     "lodash": "^4.0.0"
   },
   "peerDependencies": {
-    "graphql": "^0.5.0"
+    "graphql": "^0.5.0 || ^0.6.0"
   },
   "devDependencies": {
     "babel": "^5.8.29",