feat: update ESLint to support newer JS syntax

Author: MaxGenash

.eslintrc

@@ -1,16 +1,14 @@
 {
   "parserOptions": {
-    "ecmaVersion": 6,
-    "sourceType": "module"
-  },
-  "ecmaFeatures": {
-    "modules": true
+    "ecmaVersion": 2018, // suppport syntax features (like Object spread operator) up to es2018
+    "sourceType": "module",
+    "ecmaFeatures": {
+      "impliedStrict": true
+    }
   },
   "env": {
-    "node": true
-  },
-  "globals": {
-
+    "node": true,
+    "es2017": true // suppport globals (like Promise) up to es2017 (es2018 doesn't have new globals)
   },
   "rules": {
     "curly": 2,

package.json

@@ -36,7 +36,7 @@
   },
   "devDependencies": {
     "code": "^1.4.0",
-    "eslint": "^2.7.0",
+    "eslint": "^6.8.0",
     "eslint-config-airbnb": "^6.2.0",
     "lab": "^13.0.1",
     "sinon": "^1.17.2"

test/helpers/pluck.js

@@ -14,8 +14,8 @@ describe('pluck helper', function() {
 
     var context = {
         users: [
-          { 'user': 'barney', 'age': 36 },
-          { 'user': 'fred',   'age': 40 }
+            { 'user': 'barney', 'age': 36 },
+            { 'user': 'fred',   'age': 40 }
         ]
     };