chore(package): update eslint to version 6.6.0

Closes #7

Author: greenkeeper[bot]

package.json

@@ -33,7 +33,7 @@
     "babel-preset-env": "^1.6.1",
     "chai": "^4.1.2",
     "chai-things": "^0.2.0",
-    "eslint": "^4.16.0",
+    "eslint": "^6.6.0",
     "eslint-config-prettier": "^2.9.0",
     "eslint-config-standard": "^11.0.0-beta.0",
     "eslint-plugin-import": "^2.8.0",