chore(package): update standard to version 7.1.2

Author: greenkeeperio-bot

package.json

@@ -10,7 +10,7 @@
     "os-homedir": "^1.0.1"
   },
   "devDependencies": {
-    "standard": "^6.0.8",
+    "standard": "^7.1.2",
     "semantic-release": "^4.3.5",
     "greenkeeper-postpublish": "^1.0.0"
   },