message: remove dupe ethereumjs-util
diff: "ethereumjs-util": "^5.1.2",
  "idna-uts46": "^1.1.0",
  "lodash": "^4.17.4",
  - "ethereumjs-util": "^5.1.2",
  "ethereumjs-wallet": "^0.6.0",
  "prop-types": "^15.5.8",
  "react": "^15.4.2",
  