chore(package): update eslint to version 6.2.0

Closes #8

Author: greenkeeper[bot]

package.json

@@ -19,7 +19,7 @@
     "babel-cli": "^6.24.1",
     "babel-eslint": "^8.0.0",
     "babel-preset-flow": "^6.23.0",
-    "eslint": "^4.0.0",
+    "eslint": "^6.2.0",
     "flow-bin": "^0.53.0",
     "tape": "^4.6.3"
   }