feat: update to config compliant with ember 3.9

Author: GreatWizard

ember.js

@@ -7,7 +7,6 @@ module.exports = {
     server: true, // mirage
     withFeature: true // feature flag
   },
-
   parserOptions: {
     ecmaVersion: 2017,
     sourceType: "module"
@@ -26,20 +25,36 @@ module.exports = {
         ".eslintrc.js",
         ".template-lintrc.js",
         "ember-cli-build.js",
+        "index.js",
         "testem.js",
         "blueprints/*/index.js",
         "config/**/*.js",
+        "tests/dummy/config/**/*.js",
         "lib/*/index.js",
         "server/**/*.js"
       ],
+      excludedFiles: [
+        "addon/**",
+        "addon-test-support/**",
+        "app/**",
+        "tests/dummy/app/**"
+      ],
       parserOptions: {
         sourceType: "script",
         ecmaVersion: 2015
       },
       env: {
         browser: false,
         node: true
-      }
+      },
+      plugins: ["node"],
+      rules: Object.assign(
+        {},
+        require("eslint-plugin-node").configs.recommended.rules,
+        {
+          // add your custom rules and overrides for node files here
+        }
+      )
     }
   ]
 }

package.json

@@ -8,9 +8,10 @@
     "eslint-plugin-ember": "6.x.x",
     "eslint-plugin-ember-suave": "1.x.x",
     "eslint-plugin-es5": "1.x.x",
+    "eslint-plugin-node": "9.x.x",
     "eslint-plugin-prettier": "3.x.x",
     "prettier": "1.x.x",
-    "prettier-eslint-cli": "4.x.x"
+    "prettier-eslint-cli": "5.x.x"
   },
   "files": [
     "core.js",