Use github lint and fix the errors reported when linting

Author: bnjamin

package.json

@@ -11,7 +11,7 @@
   ],
   "scripts": {
     "clean": "rm -rf dist",
-    "lint": "eslint src/ test/ && flow check",
+    "lint": "github-lint",
     "prebuild": "npm run clean && npm run lint && mkdir dist",
     "build": "rollup -c && cp src/combobox-nav.js.flow dist/combobox-nav.esm.js.flow && cp src/combobox-nav.js.flow dist/combobox-nav.umd.js.flow",
     "test": "karma start test/karma.config.js",

prettier.config.js

@@ -1 +1,2 @@
+/* @flow */
 module.exports = require('eslint-plugin-github/prettier.config')

rollup.config.js

@@ -26,4 +26,3 @@ export default {
     })
   ]
 }
-