Add turbo:extendedHtml to item (#8)

lib/index.js

@@ -146,6 +146,7 @@ class TR {
             itemValues.push({_attr: {'turbo': item.turboEnabled ? 'true' : 'false'}});
             itemValues.push({link: item.url});
 
+            self.pushIfConditionTrue(item.extendedHtml, itemValues, {'turbo:extendedHtml': 'true'});
             self.pushIfConditionTrue(item.turboSource, itemValues, {'turbo:source': item.turboSource});
             self.pushIfConditionTrue(item.turboTopic, itemValues, {'turbo:topic': item.turboTopic});
             self.pushIfConditionTrue(item.date, itemValues, {pubDate: new Date(item.date).toUTCString()});
@@ -218,6 +219,7 @@ class TR {
             turboTopic: data.turboTopic || '',
             goals: data.goals || [],
             turboEnabled: data.turboEnabled !== undefined ? data.turboEnabled : true,
+            extendedHtml: data.extendedHtml || false,
         };
     }
 }