chore(package): update flow-bin to version 0.60.1

Closes #6

Author: greenkeeper[bot]

package.json

@@ -17,7 +17,7 @@
     "babel-eslint": "^8.0.0",
     "babel-preset-flow": "^6.23.0",
     "eslint": "^4.0.0",
-    "flow-bin": "^0.53.0",
+    "flow-bin": "^0.60.1",
     "keccak": "^1.3.0",
     "keccakjs": "^0.2.1",
     "secp256k1": "^3.3.0",