chore(package): update standard to version 8.0.0 (#42)

https://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -55,7 +55,7 @@
     "coveralls": "^2.11.8",
     "mocha": "^3.0.0",
     "nyc": "^8.1.0",
-    "standard": "^7.0.1",
+    "standard": "^8.0.0",
     "standard-version": "^2.1.2"
   },
   "files": [