chore(package): update prettier to version 2.0.1

Closes #39

Author: greenkeeper[bot]

package.json

@@ -12,7 +12,7 @@
     "husky": "^0.14.0",
     "jest": "^19.0.2",
     "lint-staged": "^4.0.0",
-    "prettier": "^1.0.0",
+    "prettier": "^2.0.1",
     "semantic-release": "^7.0.1"
   },
   "babel": {