Smart Search: Fixes "Expand Advanced Search" option

### The issue:
When the "Expand Advanced Search" option is selected, the Advanced Search form should be displayed in its expanded view: this does not happens.

### The fix:
Add the `in` class to the advancedSearch &lt;div&gt; when the option is selected

### More issues **NOT SOLVED** by this PR
- The JS code for toggling the Advanaced Search form is not functional and can be eliminated (the functionality is guaranteed by BS `data-toggle`)
- The JS that should disable fields not used in the search when submitting the form (and thus clean-up the search URL) is not working and search URLs are littered by unused options (e.g.: `&Search=&t[]=&t[]=&t[]=`)