Update Prettier to v1 (#2465)

* Update Prettier to v1

* Update package.json

Author: ianschmitz

package.json

@@ -19,7 +19,7 @@
     "lerna": "2.0.0-beta.38",
     "lerna-changelog": "^0.2.3",
     "lint-staged": "^3.3.1",
-    "prettier": "^0.21.0"
+    "prettier": "^1.5.2"
   },
   "lint-staged": {
     "*.js": [