Improve dataTables integration within the app:

- Manage lib through NPM
- Move portal / Bootstrap files back to the itop-portal-base module (not managed through NPM yet)
- Fix SCSS classes for the backoffice as it was based on the bootstrap CSS classes which are not there anymore

Note: jQuery is included as a dependency, will check with the team if we can force it not to be retrieved

node_modules/jquery/src/var/document.js

@@ -0,0 +1,5 @@
+define( function() {
+	"use strict";
+
+	return window.document;
+} );