chore(package): update graphql-tools to version 6.0.1

Closes #7

Author: greenkeeper[bot]

package.json

@@ -54,7 +54,7 @@
     "eslint-plugin-import": "^2.7.0",
     "eslint-plugin-prettier": "^2.1.2",
     "graphql": "^0.11.7",
-    "graphql-tools": "^2.5.1",
+    "graphql-tools": "^6.0.1",
     "husky": "^0.14.3",
     "jest": "^21.2.1",
     "nodemon": "^1.11.0",