Extraction: Rewrite item_extraction for better error handling and readability, rename extracted names for more consistency

youtube/templates/playlist.html

@@ -54,8 +54,9 @@
         <h2 class="playlist-title">{{ title }}</h2>
         <a class="playlist-author" href="{{ author_url }}">{{ author }}</a>
         <div class="playlist-stats">
-            <div>{{ views }}</div>
-            <div>{{ size }} videos</div>
+            <div>{{ video_count|commatize }} videos</div>
+            <div>{{ view_count|commatize }} views</div>
+            <div>Last updated {{ time_published }}</div>
         </div>
         <div class="playlist-description">{{ common_elements.text_runs(description) }}</div>
     </div>