Thesauri in metadata details

[etj]

Is your feature request related to a problem? Please describe.

Thesauri keywords are displayed along with free keyword, without any categorization.

Describe the solution you'd like

Thesauri keywords should be grouped, showing the thesaurus they belong to.
This change should be implemented in both:

• layer info
• metadata detail page.

Note that thesauri titles and keywords should be localized:

• use ThesaurusLabel for localization and fallback to Thesaurus.title;
• use use ThesaurusKeywordLabel for localization and fallback to ThesaurusKeyword.alt_title

e.g.:

This could be implemented by placing entries in a <ul> :

<dd>
   <ul>
      <li>free kw 1</li>
      <li>free kw 2</li>
      <li>free kw 3</li>
      <li>Thesaurus title 1
         <ul>
            <li>item1</li>
            <li>item2</li>
         </ul>
      </li>
      <li>Thesaurus title 2
         <ul>
            <li>item3</li>
            <li>item4</li>
         </ul>
      </li>
   </ul>   
</dd>

Describe alternatives you've considered
N/A

Additional context
N/A

[mattiagiupponi]

Here is an example of how the keywords will be displayed:
Layer info:

Medatata details:

Is this fine @etj ?

[etj]

It looks really good to me.
I would like to hear from @giohappy and @afabiani about the layer info page, where keywords may take a very large portion of the page.