chore(package): update eslint to version 6.8.0

Closes #38

Author: greenkeeper[bot]

package.json

@@ -24,7 +24,7 @@
     "babel-preset-es2015": "^6.9.0",
     "babelify": "^7.3.0",
     "browserify": "^14.1.0",
-    "eslint": "^4.1.0",
+    "eslint": "^6.8.0",
     "husky": "^0.14.0",
     "jest": "^21.0.0",
     "lint-staged": "^4.0.0",