Replace ES6 by Webpack in the integration docs (#5555)

docs/getting-started/integration.md

@@ -2,13 +2,6 @@
 
 Chart.js can be integrated with plain JavaScript or with different module loaders. The examples below show how to load Chart.js in different systems.
 
-## ES6 Modules
-
-```javascript
-import Chart from 'chart.js';
-var myChart = new Chart(ctx, {...});
-```
-
 ## Script Tag
 
 ```html
@@ -18,6 +11,13 @@ var myChart = new Chart(ctx, {...});
 </script>
 ```
 
+## Webpack
+
+```javascript
+import Chart from 'chart.js';
+var myChart = new Chart(ctx, {...});
+```
+
 ## Common JS
 
 ```javascript