Add bundle files (#50)

bower.json

   "authors": [
     "Vaadin Ltd"
   ],
-  "main": "",
+  "main": "vaadin.html",
   "license": [
     "Apache-2.0",
     "https://vaadin.com/license/cval-3.0"

package.json

     "@vaadin/vaadin-grid-pro": "^2.0.3",
     "@vaadin/vaadin-rich-text-editor": "^1.0.4"
   },
-  "files": [],
+  "files": [
+    "vaadin.js"
+  ],
   "scripts": {
     "version": "node update-core-version.js && git add bower.json"
   },

vaadin.html

+<link rel="import" href="../vaadin-core/vaadin-core.html">
+<link rel="import" href="../vaadin-board/vaadin-board.html">
+<link rel="import" href="../vaadin-charts/vaadin-chart.html">
+<link rel="import" href="../vaadin-confirm-dialog/vaadin-confirm-dialog.html">
+<link rel="import" href="../vaadin-cookie-consent/vaadin-cookie-consent.html">
+<link rel="import" href="../vaadin-crud/vaadin-crud.html">
+<link rel="import" href="../vaadin-grid-pro/vaadin-grid-pro.html">
+<link rel="import" href="../vaadin-grid-pro/vaadin-grid-pro-edit-column.html">
+<link rel="import" href="../vaadin-rich-text-editor/vaadin-rich-text-editor.html">

vaadin.js

+import '@vaadin/vaadin-core/vaadin-core.js';
+import '@vaadin/vaadin-board/vaadin-board.js';
+import '@vaadin/vaadin-charts/vaadin-chart.js';
+import '@vaadin/vaadin-confirm-dialog/vaadin-confirm-dialog.js';
+import '@vaadin/vaadin-cookie-consent/vaadin-cookie-consent.js';
+import '@vaadin/vaadin-crud/vaadin-crud.js';
+import '@vaadin/vaadin-grid-pro/vaadin-grid-pro.js';
+import '@vaadin/vaadin-grid-pro/vaadin-grid-pro-edit-column.js';
+import '@vaadin/vaadin-rich-text-editor/vaadin-rich-text-editor.js';