Issue 7398 - Add recommended filterlists dropdown

In order to reuse the dropdown component, I've implemented few changes:

• the custom element accepts a data-text and an optional data-expanded to define the messages to show, instead of using hard coded language related text
• the component accept a list of items with group items too, which are used simply as list separators, and are not responsible for changes (i.e. not clickable)
• the component has an autoclose boolean attribute that (IMO) helps UX since while items are being added the component would keep moving otherwise, and it wouldn't be instantly visible which filter has been added

See #129 (closed)