Feat/webpack (#2998)

* First commit

* Removed govuk for webpack. Modernized javascript importing. Removed dead js

* Fixed tests, a few styling bugs

* Fixed some table errors and regenerated backstop ref images

* Updated tests for coverage

* Changes from carlo suggestions

babel.config.js

@@ -1,3 +1,9 @@
 module.exports = {
-    presets: ['@babel/preset-env'],
+  presets: [
+    ['@babel/preset-env', {
+      targets: {
+        node: 'current'
+      }
+    }]
+  ]
 };