chore(package): update eslint to version 6.1.0

Closes #191

Author: greenkeeper[bot]

package.json

@@ -17,7 +17,7 @@
     "css-loader": "^0.28.9",
     "dom-storage": "^2.0.2",
     "ejs-loader": "^0.3.0",
-    "eslint": "^4.18.0",
+    "eslint": "^6.1.0",
     "extract-text-webpack-plugin": "^3.0.2",
     "file-loader": "^1.1.6",
     "git-prepush-hook": "^1.0.1",