Bitcoin Paper: Add Italian Translation

Italian translation written by Terzim and reviewed by Saïvann and
Harding.

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_templates/bitcoin-paper.html

@@ -26,12 +26,15 @@ <h1>{% translate pagetitle %}</h1>
 UTF-8 alphabetical order
 {% endcomment %}
 <ul>
-<li><a href="/bitcoin.pdf">English original</a></li>
+<li><b><a href="/bitcoin.pdf">English original</a></b></li>
 
 <li><a href="/files/bitcoin-paper/bitcoin_es.pdf">Español (España)</a> {% translate translated_by %} <a href="https://github.com/breathingdog">Breathingdog</a></li>
 
 <li><a href="/files/bitcoin-paper/bitcoin_es_latam.pdf">Español (Latinoamericano)</a> {% translate translated_by %} <a href="https://github.com/gubatron">Angel León</a></li>
 
+<li><a href="/files/bitcoin-paper/bitcoin_it.pdf">Italiano</a> {% translate translated_by %}
+ <a href="https://github.com/terzim">Terzim</a></li>
+
 <li><a href="/files/bitcoin-paper/bitcoin_ru.pdf">Русский</a> {% translate translated_by %} <a href="https://github.com/arvicco">Ar Vicco</a></li>
 </ul>