Update dependency prettier to v1.13.7 (#81)

Author: renovate[bot]

package-lock.json

@@ -82,7 +82,7 @@
     "json-loader": "0.5.7",
     "lint-staged": "7.2.0",
     "mocha": "5.2.0",
-    "prettier": "1.12.1",
+    "prettier": "1.13.7"
     "react": "16.3.2",
     "react-addons-test-utils": "15.6.2",
     "react-codemirror2": "5.1.0",