New: Cleanup UI tooling, Update to Webpack 4, Gulp 4 (#655)

* New: Webpack 4

* New: Gulp 4

* New: Transpile UI for old browsers

Co-Authored-By: Mark McDowall <markus101@users.noreply.github.com>

frontend/src/Store/Actions/addArtistActions.js

@@ -1,5 +1,4 @@
 import _ from 'lodash';
-import $ from 'jquery';
 import { createAction } from 'redux-actions';
 import { batchActions } from 'redux-batched-actions';
 import monitorOptions from 'Utilities/Artist/monitorOptions';
@@ -120,12 +119,12 @@ export const actionHandlers = handleThunks({
     const items = getState().addArtist.items;
     const newArtist = getNewArtist(_.cloneDeep(_.find(items, { foreignArtistId })), payload);
 
-    const promise = $.ajax({
+    const promise = createAjaxRequest({
       url: '/artist',
       method: 'POST',
       contentType: 'application/json',
       data: JSON.stringify(newArtist)
-    });
+    }).request;
 
     promise.done((data) => {
       dispatch(batchActions([