Upgraded babel and webpack to support async keyword with preset-env over es2015

.babelrc

@@ -1,6 +1,8 @@
 {
   "presets": [
-    ["es2015", { "modules": false }]
+    ["@babel/preset-env", {
+      "useBuiltIns": false
+    }]
   ],
-  "plugins": ["transform-object-rest-spread"]
+  "plugins": ["@babel/plugin-transform-runtime"]
 }

package.json

@@ -23,9 +23,11 @@
     "vuex": "^3.1.0"
   },
   "devDependencies": {
-    "babel-core": "^6.22.1",
+    "@babel/core": "^7.4.5",
-    "babel-loader": "^7.1.1",
+    "@babel/plugin-transform-runtime": "^7.4.4",
-    "babel-preset-es2015": "^6.0.0",
+    "@babel/preset-env": "^7.4.5",
+    "@babel/runtime": "^7.4.5",
+    "babel-loader": "^8.0.6",
     "cross-env": "^3.0.0",
     "css-loader": "^0.25.0",
     "documentation": "^11.0.0",

webpack.config.js

@@ -23,6 +23,9 @@ module.exports = {
       {
         test: /\.js$/,
         loader: 'babel-loader',
+        options: {
+          presets: ['@babel/preset-env']
+        },
         exclude: /node_modules/
       },
       {