chore(package): update eslint to version 6.7.1

Closes #33

Author: greenkeeper[bot]

package.json

@@ -49,7 +49,7 @@
     "cpy-cli": "^1.0.1",
     "cross-env": "^5.1.3",
     "del-cli": "^1.1.0",
-    "eslint": "^4.13.1",
+    "eslint": "^6.7.1",
     "eslint-config-airbnb-base": "^12.1.0",
     "eslint-config-prettier": "^2.9.0",
     "eslint-plugin-import": "^2.8.0",