chore(package): update eslint to version 6.2.1

Closes #67

Author: greenkeeper[bot]

package.json

@@ -52,7 +52,7 @@
     "buble": "0.15.2",
     "dependency-check": "2.9.1",
     "doctoc": "1.3.0",
-    "eslint": "4.5.0",
+    "eslint": "6.2.1",
     "eslint-config-eslint": "4.0.0",
     "faucet": "0.0.1",
     "husky": "0.14.3",