chore(package): update eslint to version 6.6.0

Closes #7

Author: greenkeeper[bot]

package.json

@@ -49,7 +49,7 @@
     "babel-eslint": "^10.0.1",
     "bdd-stdin": "^0.2.0",
     "chai": "^4.1.2",
-    "eslint": "^5.1.0",
+    "eslint": "^6.6.0",
     "mocha": "^6.0.0",
     "prettier": "^1.13.7",
     "prettier-eslint": "^8.8.2"