chore(package): update assert-diff to version 1.1.1

https://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -49,7 +49,7 @@
     "sqlstring": "^2.2.0"
   },
   "devDependencies": {
-    "assert-diff": "^1.0.1",
+    "assert-diff": "^1.1.1",
     "eslint": "3.17.0",
     "eslint-plugin-markdown": "^1.0.0-beta.2",
     "husky": "^0.13.0",