title: Group by and format a list of authors
body: <p>given the following javascript Object</p>
  
  <pre><code>[
    {"name":"Albert Trucmuche","role":"Textes","licence":"CC BY-NC-ND"},
    {"name":"Nina Machin","role":"Illustrations","licence":"Tous droits réservés"},
    {"name":"Roberta Bidulle","role":"Textes","licence":"CC BY-NC-ND"}
  ]
  </code></pre>
  
  <p>How can I get this?</p>
  
  <pre><code>"Albert Trucmuche et Roberta Bidulle &lt;small&gt;CC BY-NC-ND&lt;/small&gt;&lt;br&gt;Illustrations: Nina Machin"
  </code></pre>
  
  <p>So the general idea is to group authors first by medium (Textes, Illustrations, etc.) then by licence. Then format am HTML string that gracefully join the authors (using commas and "et" if it is the last author).</p>
  
  <p>The licence does not need to appear if it is "Tous droits réservés".</p>
  
  <p>I'm open to other HTML+CSS structure/styling if it makes things easier.</p>
  
  <p>Thanks</p>